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Chapter 2 Reports of the Visiting Review Committee for Individual Research Fields
List of Visiting Review Committee for Individual Research Fields *Chairman **Secretary (1) Cosmic Radio Astronomy (Nov. 8th - 10th, 1995) *Akito Arima (President of RIKEN: Nuclear Physics) Hiroo Inokuchi (former Director of Okazaki National Research Institutes: Molecular Chemistry) Malcolm Longair (Jacksonian Professor of Natural Philosophy, University of Cambridge, England: Celestial Mechanics) Yasuo Tanaka (Honorary Professor of The Institute for Space and Aeronautics Sciences: X-ray Astronomy) Paul Vanden Bout (Director of the National Radio Astronomy Observatory, USA: Radio Astronomy) (2) Theoretical Astrophysics and Astronomical Data Analysis Center (Dec. 26th - 27th, 1996) *Masaki Morimoto (Professor, Kagoshima University,: Radio Astronomy) Sadanori Okamura (Professor, the University of Tokyo: Optical Astronomy) Shoji Kato (Professor, Kyoto University: Theoretical Astrophysics) **Shuji Sato (Professor, Nagoya University: Infrared Astronomy) Tetsuyuki Yukawa (Professor, Graduate University for Advanced Studies: Elementary Particle Physics) (3) Division of Astrometry and Celestial Mechanics, Division of Earth Rotation and related fields (Feb. 25th - 25th, 1997) Jiro Arafune (Institute for Cosmic Ray Research, the University of Tokyo: Cosmic-Ray Physics) *Satoru Ikeuchi (Professor, Osaka University: Theoretical Astrophysics) Hajime Inoue (Professor, the Institute for Space and Aeronautics Sciences: X-ray Astronomy) Toshihiro Omodaka (Professor, Kagoshima University: Radio Astronomy) Yoshio Kubo (Associate Director, the ninth-district Division, Maritime Safety Agency: Celestial Mechanics) Mineo Kumazawa (Professor, Nagoya University: Geophysics) **Makoto Tosa (Professor, Tohoku University: Theoretical Astrophysics) (4) Solar Research (Apr. 8th - 9th, 1997) *Hirito Tabara (Professor, Utsunomiya University: Radio Astronomy) Hiroki Kurokawa (Professor, Kyoto University: Solar Physics) Toshio Terasawa (Professor, the University of Tokyo, Magnetospheric Physics) **Fumiaki Makino (Professor, The Institute for Space and Aeronautics Sciences: X-ray Astronomy Susumu Kokubun (Professor, the Solar-Terrestrial Environment Laboratory: Solar-Terrestrial Physics) (5) Optical and Infrared Astronomy (Apr. 22nd-23rd, 1997) *Haruyuki Okuda (Professor, Institute of Space and Astronautical Science: Infrared Astronomy) Dai'ichiro Sugimoto (Professor, University of Air: Theoretical Astrophysics) Tuneyoshi Kamae (Professor, the University of Tokyo, Elementary Particle Physics) Humio Takahara (Professor, Metropolitan University: Theoretical Astrophysics) **Ken'ichi Wakamatsu (Professor, Gifu University: Optical Astronomy)
1. Report of the Visiting Review Committee on the Cosmic Radio Observing Facilities, Nobeyama Radio Observatory Visiting Review Committee (Chairman: Akito Arima) January 1996 EXECUTIVE SUMMARY The Nobeyama Radio Observatory is one of the world's leading observatories for studies in the millimeter and submillimeter wave bands. The 45-m Telescope and the Nobeyama Millimeter Array have unique capabilities and have enabled Japanese astronomers to make outstanding contributions to many diverse fields of astronomy ranging from the origin of stars and planetary systems, to the discovery of supermassive black holes in galactic nuclei, to observations bearing on cosmology and the origin of galaxies. These achievements have been built upon imaginative and innovative technology programs. The facilities are currently at a peak of productivity and are being very well utilized by the Japanese community and by guest observers from other countries. The fields of millimeter astronomy are highly competitive, and to maintain the facilities at the forefront of astronomical capability, the Nobeyama astronomers and technologists have proposed a cost-effective program of upgrades to the present facilities which will enable the 45-m Telescope to be incorporated into the Nobeyama Millimeter Array. We recommend very strongly that these upgrades be funded and carried out with the greatest urgency. They will provide unique capabilities in terms of angular resolution and sensitivity until the next generation of large millimeter arrays comes into operation. The next generation of millimeter telescopes will involve large numbers of telescopes on outstanding sites for millimeter and submillimeter astronomy. The Nobeyama astronomers have developed plans for a Large Millimeter Submillimeter Array which has been adopted by the Japanese astronomical community as the next large ground-based project to follow the completion of the Subaru 8-m optical/infrared telescope. The Visiting Review Committee (hereafter called Committee) recognizes that the plans for the Large Millimeter Submillimeter Array are ambitious and represent the natural successor to the present generation of millimeter and submillimeter facilities. The Committee recommends enthusiastically that funds be made available for feasibility studies to identify the optimum site and the nature of the many technical challenges to be overcome and to develop a definitive plan which can be presented for detailed scrutiny within the next two years. The Committee noted that several opportunities for international collaboration should be investigated to identify areas of common interest and potential collaboration. The Committee was made aware of the great pressure upon staff of the Observatory. The program is being operated by a staff which is too small to fully exploit the scientific potential of the facilities. The success of the Observatory, which has less than half the staff of comparable facilities overseas, has been due to superhuman efforts on the part of the scientific and technical staff. The Committee recommends that there should be an immediate increase in the staff, particularly in the areas of research and development, hardware construction and maintenance, telescope operations, and support astronomers. Japanese astronomy has made enormous advances over the last two decades and ambitious plans are being made for the future. The Committee believes that the size of the university community of astronomers is unusually small compared with similar countries and that it is essential to expand the number of astronomers in order to obtain full advantage from Japan's major investment in astronomy. The Committee notes that the shortage of graduate students, common to all scientific disciplines in Japan, is particularly acute in astronomy. The numbers of graduate students in astronomy should be at least doubled immediately, and the Japanese universities should be encouraged to expand their astronomy programs and develop new departments of modern astronomy. The communication of the achievements of the Nobeyama Observatory to the general public is a vital part of the program of the Observatory. The Observatory attracts a large number of the public as visitors, but the Observatory should enhance its role in public outreach and in public education. Summary of Recommendations The Committee recommends: 1. the funding of the proposed plan of upgrades to the 45-m Telescope and the Nobeyama Millimeter Array, leading to the Rainbow facility; 2. the funding of feasibility studies for the Large Millimeter Submillimeter Array, leading to a definitive plan within the next two years; 3. an immediate increase in the staff of the Nobeyama Radio Observatory; 4. that immediate steps be taken to increase the size of the university astronomical community in Japan and, in particular, that the number of graduate students and postdocs in astronomy be at least doubled; 5. that the program of public education and outreach of the Nobeyama Radio Observatory be enhanced. Introduction The Nobeyama Radio Observatory (NRO) is one of the major divisions of the National Astronomical Observatory of Japan (NAOJ). The Visiting Review Committee for the NRO was invited by the Director of the NAOJ to carry out a review of the NRO with the following terms of reference: 1. to evaluate the scientific and technical achievements of the NRO and its contributions to the domestic and world community; 2. to examine the research and the engineering strategies developed by the NRO which are leading to the Large Millimeter Submillimeter Array (LMSA) project, and 3. to advise on system improvements and/or strategy modifications to be pursued by NRO in future planning. The members of the Committee were: Professor Akito Arima, President of RIKEN; Professor Hiroo Inokuchi, former Director of Okazaki National Research Institutes; Professor Malcolm Longair, Jacksonian Professor of Natural Philosophy, University of Cambridge, England; Professor Yasuo Tanaka, Honorary Professor of ISAS; Professor Paul Vanden Bout, Director of the National Radio Astronomy Observatory, USA. The contact person with the Council of the NAOJ was: Professor Yoshihide Kozai, former Director of the NAOJ. The Observers at the discussion of the Committee were: Dr. David Swinbanks, Asia-Pacific Editor and Publisher, "Nature," Japan Office; Ms. Mariko Takahashi, Science Section Journalist, "Asahi-shimbun," Osaka. The meetings of the Committee took place at the NRO 8 to 10 November 1995. The Committee was provided with comprehensive material concerning all aspects of the activities of the NRO, and we commend the Observatory on the excellence of the report. Development of the NRO The NRO is one of the world's leading observatories in the field of millimeter and submillimeter astronomy. The Observatory has played a unique role in Japanese astronomy. It was the first major observatory built and developed with the aim of bringing Japanese observational astronomy and astrophysics to the forefront of contemporary research. The NRO was established in 1978 as the first common-user facility of the Tokyo Astronomical Observatory, which was a research institute of the University of Tokyo. The project began with only four staff members, but this number grew as the two major instruments of the Observatory came into operation. These were the 45-m Telescope which came into operation in 1982 and the 5-element Nobeyama Millimeter Array (NMA) which was commissioned in 1985. These two telescopes have been outstandingly successful and have without question led to Japan becoming a world leader in the fields of millimeter and submillimeter astronomy. The facilities have attracted many foreign guest observers and have led to important international collaborations with many countries. In 1988, the NRO was incorporated into the newly founded NAOJ, which was formed by combining a number of facilities and functions of the Tokyo Astronomical Observatory with other related facilities. In particular, the NAOJ became responsible for the Subaru 8-m optical/infrared telescope, which is currently well advanced in its construction in Hawaii. The NAOJ is responsible for all Japanese national facilities in ground-based astronomy and also collaborates in space missions with the Institute of Space and Astronomical Sciences (ISAS). The range of astronomy supported by NAOJ is very wide indeed and includes divisions for optical and infrared astronomy, including the Subaru telescope, solar physics, astrometry and celestial mechanics, theoretical astrophysics, radio astronomy (including all the activities of the NRO), and earth rotation. Overall, the NAOJ has about 278 staff members, and of these 46 are members of the NRO. Since its founding in 1988, a number of new programs have been undertaken. The largest of these is the Subaru project. In addition, a radio heliograph was completed in 1992. Other ongoing projects include the space VLBI project VSOP, which is carried out jointly with ISAS and which will be launched in 1996, and the 300-m gravitational wave interferometer. Thus, the NRO is set within a very active and ambitious program of contemporary astronomy and astrophysics. Advances Made at the NRO Technical Advances From the time of its commissioning, the 45-m Telescope has been a premier instrument for millimeter astronomy. In addition to being the largest telescope in the world for observations in the 2 to 5 mm waveband, the instrumentation program has been world-leading since its inception. The acousto-optical spectrometer has the largest number of channels (32,000) of any millimeter telescope, and this has provided the facility with unique powers in the search for interstellar molecules and in projects in which a wide bandwidth is needed to observe large velocity spread in celestial objects. The group has been at the forefront of introducing HEMT amplifiers and SIS technology into millimeter wave receivers. The most recent success has been the development of the first 2x2 SIS array receivers which has resulted in a factor of four increase in the rate at which spectral-line data can be obtained. The next step is the development of 5x5 SIS array receivers which will provide a further order of magnitude improvement in the speed of acquisition of millimeter-line data. The surface accuracy of the 45-m Telescope has been improved through the use of holographic techniques for setting its surface. As a result, the telescope can now operate with high efficiency at wavelengths as short as 1.3 mm under benign observing conditions. At these high frequencies, the telescope is subject to pointing errors because of windshake, and so the team is developing real-time adaptive adjustment of the antenna to improve the pointing. The NMA has achieved world-leading capabilities through the development of dual-frequency SIS receivers and the expansion of the FX correlator bandwidth to 320 MHz. Currently the interferometer operates at 100 GHz and 150 GHz, and it will soon be operational at 230 GHz. An important development has been the construction of a sixth 10-m antenna with a very high surface accuracy. The additional antenna enables the telescope to have 15 independent baselines and improve the u-v coverage. It is also a prototype for the LMSA. The most exciting development currently underway is the incorporation of the 45-m Telescope into the array. The project, known as Rainbow, will greatly increase the sensitivity of the interferometer system, making it the leading instrument for millimeter interferometry over the baselines available. Science Advances The millimeter wave telescopes have made a very wide range of different types of observation, which span the whole of millimeter astronomy. The Committee regards the whole program as being world-class astronomy with a number of areas in which particularly outstanding contributions have been made. Among the latter category, we highlight: (1) Interstellar chemistry. Through the wide bandwidths available on the spectrometers, the discovery of interstellar molecular lines and their identification with molecular species by laboratory spectroscopy has been a feature of the science program. Fifteen different kinds of unstable and stable molecules have been discovered over the last 10 years. Molecular spectroscopy is an area in which there has been much activity in Japan over the last 60 years, and there is great potential for increased cooperation between these university based groups and the NRO. (2) The discovery of protostellar discs. The high resolution of the NMA has enabled observations to be made of molecular rings about protostellar objects. The axes of these discs are found to be parallel to the bipolar molecular outflows which are found wherever star formation is observed. These observations provide crucial clues for understanding the formation of stars and of planetary systems. (3) The mass distribution of clumps within giant molecular clouds and the initial mass function for stars. A map of the closest giant molecular cloud to the Earth, the Orion Molecular Cloud, has revealed a large number of compact knots which are the sites of star formation. The mass function of these knots is similar to the initial mass function of stars, inferred from the statistics of stars of different types in the Galaxy. This is an important clue to the means by which stars of different masses are formed. (4) The study of masers in the Galactic bulge. Molecular masers are tracers of the structure of our Galaxy. This approach has been used to define the structure of the central bulge of our Galaxy and shown that it is probably a bar, rather than a spheroidal distribution. By extension, the maser sources can be used define the large scale structure of the Galaxy as a whole. (5) The astrophysics of the central regions of our Galaxy. Observations have been made in molecular lines and in continuum radiation of the very central regions of our Galaxy. These have revealed the strange arc structures as well as the discovery of a new type of source which has only been observed by its polarized radio emission. This polarized jet is presumably associated with high energy activity in the nucleus of our Galaxy. (6) Star formation in nearby galaxies. Mapping of the central regions of galaxies by their molecular line emission has been carried out very completely for a number of nearby spiral galaxies. These show clearly the relation between the distribution of molecular gas and the optical spiral structure, illustrating the compression of the molecular gas by the passage of a spiral density wave. (7) Millimeter VLBI and the cores of quasars. The Nobeyama 45-m Telescope has successfully participated in millimeter VLBI observations of luminous radio quasars. The map of the radio quasar 3C 273 has an angular resolution of about 100 microarcsecs, the highest angular resolution yet obtained in VLBI. These observations have shown that the alignment of the jet extends into the very core of the quasar. (8) The discovery of the black hole in NGC 4258. One of the most important observations in high energy astrophysics has been the discovery of convincing evidence for a supermassive black hole in the galaxy NGC 4258. The key discovery was the detection of very high velocity water vapor sources by the Nobeyama 45-m Telescope in the nucleus of the galaxy. Subsequent observations using the Very Long Baseline Array showed that the water vapor masers are located in a ring rotating at a very high speed about the galactic nucleus. The inferred mass of the black hole is about 3.6x107 solar masses. Although this is not the most massive black hole yet discovered, it is by a considerable margin the highest mass density yet found in the nucleus of a galaxy, exceeding that of a dense star cluster by a factor of about 10,000. This means that the central object can only be a supermassive black hole. Planned Improvements to the NRO Telescopes The NRO has proposed a number of projects to improve the capabilities of the 45-m Telescope and the NMA. First among these is the Rainbow Project the incorporation of the 45-m Telescope into the NMA. This project will dramatically improve the sensitivity of the NMA by more than a factor of 10 by adding the collecting area of the 45-m Telescope to that of the six 10-m antennas; by resurfacing the five older 10-m antennas to match the reflector quality of the sixth, new 10-m antenna; and by expanding the correlated bandwidth from 320 MHz to 1 GHz, and eventually to 2 GHz. This project, which will give the NRO a large competitive advantage over similar facilities elsewhere in the world, has the enthusiastic endorsement of the Committee. This project is highly cost-effective and readily implemented with an increase of budget. The Committee also endorses the plans to improve the performance of the 45-m Telescope. The need for an active system to correct the pointing of the telescope in moderate wind conditions is long standing. Improvements in mapping speed by the use of array receivers have been achieved with a 4-beam system; the proposed 25-beam system will be an even more significant advance. A digital spectrometer for the 45-m Telescope is an urgent necessity, in the long term to serve the 25-beam receiver, but in general to enable more sensitive searches for the wide, weak lines characteristic of extragalactic systems. The urgency for this improvement derives from the widespread perception that extragalactic research is among the most important areas of research in astronomy, one where the 45-m Telescope can make a significant contribution. The Large Millimeter Submillimeter Array The NRO's long range future lies in the proposed LMSA. The scientific potential of the LMSA is very high in that it addresses urgent questions in modern astrophysics, such as the formation of galaxies, the structure and evolution of galaxies, the process of star formation, and the evolution of protoplanetary systems. The ability of interferometric arrays to make significant contributions in these areas is very widely recognized in world-wide astronomy. High priority plans are being made in the United States and in Europe for millimeter/submillimeter arrays. It must be emphasized that millimeter/submillimeter interferometry is often uniquely capable of addressing these questions. For example, the matter that assembles into a protogalaxy, prior to the formation of stars, can only be seen in the radiation from molecular gas and thermal dust emission, and both are best seen in the millimeter and submillimeter. The dynamics of collapse to star formation, the formation of protoplanetary disks, the process of accretion and outflow from protostellar systems, all these are enveloped by dust that obscures our view, except at the longest wavelengths the millimeter and submillimeter. Furthermore, the angular resolution that can be achieved in the millimeter and submillimeter with an interferometric array matches the requirement for subarcsecond resolution that characterizes modern astronomical observing at all wavelengths. The LMSA would consist of 50 antennas of diameter 10 meters, operating in several bands from a frequency of 40 GHz to 850 GHz. A high, dry site is required, probably in either Hawaii or the northern desert of Chile. The technology required is familiar to the NRO; their expertise resulted in the successful construction and operation of the Nobeyama Millimeter Array, and they are recognized as pioneers in their area of radio astronomy. They are able to direct the design and construction of the much larger and more capable LMSA. Japan is fortunate in having an expert team ready to compete in this active area of international astronomy. The Committee endorses this project as the next logical major project for the NRO/NAOJ. In view of the high scientific value of the LMSA project, the Committee strongly recommends that funds be made available to initiate feasibility studies. The feasibility studies should involve not only the technical issues but also the site selection and other associated problems. Because of the complexities of the project and the large scale of manpower and budget required, feasibility studies are important before requesting official approval and funding, and they are the key to the successful execution of the project. It would be worthwhile to consider a bilateral or multilateral international collaboration for the project. The Committee notes that the present user community in Japan, although vigorous and of high quality, is small compared to the speed and power with which the LMSA will produce observational data. At large foreign radio telescope facilities there is typically a corresponding large university-based user community which competes for time. For example, the U.S. Very Large Array has over 600 users per year, largely from universities. Increasing the number of astronomers in Japan, currently somewhat less than three astronomers per million population (24th in world ranking, comparable to Chile and Poland), to roughly double the current number over the next ten years would enable Japan to make better use of its investment in major astronomical facilities like Subaru and the LMSA. It would also make Japan a stronger competitor with other leading nations in world astronomical research. Staff and Budget The NRO staff, extremely small in number, have been vigorous in pursuing both scientific research and development of technology. The Committee is unanimous and enthusiastic in its praise of this research and development activity. It is most impressive that individual researchers are working both in building and improving instruments through technological developments and, at the same time, are carrying out scientific research with these instruments. The Committee believes it of crucial importance for the NRO to keep both these types of activity at a high level in the future. There was insufficient time to check fully the budget of the NRO, that is, a breakdown of the expenditure into research, maintenance, and operations. There was a discussion as to whether the budget for computer rental is reasonable in the total running cost of the Observatory, in that the fraction and size of the budget for this purpose seems to be higher than at radio observatories in the United States. The Committee, however, understands that the computer budget is used not only for support of computer control of the telescopes and observing, but also for data reduction and general scientific computing. In view of that, the budget may not be unreasonable for an Observatory the size of the NRO. Nevertheless, some thought should be given as to whether NRO's budget is being used in the most effective way. According to the Report, the breakdown of NRO permanent staff members is as follows: Researchers 17 (37%) Postdocs 8 (17%) Engineers/Technicians 15 (33%) Administrative Officials 6 (13%) ------------------------------------------ Total 46 It is remarkable that the NRO has been operating so actively in its five groups with this small staff, and that more than 400 papers have been published in the past 13 years. We also note that the NAOJ is exceptional in that its research divisions are located at several different sites, which requires some extra time and staff in its management. In particular, the number of administrative officials, 6 in the case of the NRO, is barely adequate for a single, separately located institute, and this number should be increased. It is useful to provide a comparison with the U.S. National Radio Astronomy Observatory (NRAO) with respect to the breakdown of staff. For the NRAO in the United States, the breakdown in staff classifications is: Researchers 76 (18%) Postdocs 9 (2%) Engineers/Technicians/Computing 278 (66%) Administrative/Management 58 (14%) -------------------------------------------------- Total 421 The large number of part-time staff and the work contracted to industry in part help fill the gap in technical staff at the NRO (33%) compared with twice that fraction at the NRAO (66%). Nevertheless, a heavy burden also falls on the NRO researchers and postdocs who, due to low numbers of technical staff, comprise over half the total staff at the NRO (52%) compared with only one-fifth at the NRAO (20%). In considering increases in the number of staff, it is necessary to analyze the current status of the Observatory and to seek the recognition of the Ministry of Education, Science, Sports, and Culture (Monbusho) in achieving the required increases. The following points should be taken into account: 1. In promoting science, technological developments of instruments and facilities are tightly coupled with the scientific research based on those developments. The Committee recognizes that this coupling is both effective and important. To strengthen that coupling, some top-level R&D engineers probably need to be employed directly by NRO. This, however, will require changes in the system of appointments of technicians to Institutes by Monbusho. For example, higher salaries for technicians must be offered. 2. To promote research the NRO has supported open-use of its telescopes. The Committee strongly desires the NRO to continue this policy as well as playing the role of being the leading radio astronomy institute in Japan. At the same time, the Committee recommends that the NRO ask the users from universities to be more involved in the operation and maintenance of its facilities. 3. It is commendable that at the NRO the staff members are collaborating with industrial engineers for developing instruments. The Committee highly recommends continuing this as a way for promoting research. In the future, as the deficiency in the number of NRO staff is filled up, the Committee believes this type of collaboration between industry and academic researchers will grow, especially when the effort is led by the NRO staff. 4. The number of postdoctoral fellows should be continuously increased. It is also desirable to employ as large a number of postdoctoral fellows as possible from outside the NRO. This would help increase both the size of the research community and its mobility. Sufficient numbers of tenured positions for young research associates (joshu) must also be maintained until there is sufficient growth in the number of postdoctoral fellowships and better recognition of the status of postdoctoral fellows. (Postdoctoral fellowships are a comparatively new phenomenon in Japan and they have not yet achieved the same status in the eyes of the Japanese scientific community as they have in the West.) 5. To encourage these young researchers to enthusiastically accept their responsibilities as the next generation of radio astronomers in Japan, it is necessary that the NRO provide them with living conditions which allow them to enjoy individual lives. Thus, the number of housing units for young researchers should be increased in number and size. A similar policy needs to be applied to graduate students. 6. The number of young foreign scientists currently at NRO is only three (one European and two Chinese). Although this is reasonable, considering the small staff numbers at NRO, the number should be increased and necessary accommodation for young foreign students (including their families) must be provided. (At present NRO only has two apartments to accommodate families.) University User Community The cooperation between the NRO and universities and other institutes has been successful. In the 1994-95 season, there were 114 proposals from principal investigators in universities and 57 from research institutes, apart from proposals from researchers in NAOJ (including NRO). However, the number of accepted proposals is much smaller; only 32 with principal investigators in universities and 4 with ones in research institutes. This large oversubscription shows, on the one hand, the crucial importance of the facilities in NRO, but it also indicates that facilities available for radio astronomy in Japan are still far from sufficient for a growing university-based user community. Care should be taken so that the large number of visiting users should not result in too small a share of the machine time going to the staff astronomers of NRO itself. We heard from staff astronomers of NRO that only 10 percent of their time can be used for their own research, with the rest of their time used in servicing for visiting users. This figure is too small and is not a desirable situation. It should be made possible for them to use roughly 50 percent of their time for their own research programs. The NRO is a common-user facility, but more emphasis should be put on the research activities of the NRO staff astronomers. Although their research activities are excellent, as we have already stated in the previous section of this report, we believe they could be even better if NRO staff had more time available for research. It is the responsibility of NRO staff to keep the facility in its best condition for the use of visiting astronomers. But this is not the end of the story. The visiting astronomers should also make efforts so that they can do their research without putting a heavy load on NRO staff. We propose encouraging visitors to become as familiar with the NRO facilities as NRO staff. Giving some priority in time allocation, for example, could be used as an incentive. On Graduate Students Japan suffers from a dearth of PhD students in science compared with other developed nations. The situation is particularly acute in more fundamental areas of science such as astronomy. Given this situation, NRO has done well to attract as many as 38 graduate students. Twelve of them are enrolled with the Observatory. Another 4 students from the University of Tokyo, and 8 from the Graduate University for Advanced Studies are supervised by NRO staff who act as adjunct professors. In addition, NRO staff jointly supervise 11 students from the University of Tokyo and 8 students from other universities. The ratio of graduate students to scientists at NRO is 2.2. Although the Committee regard this a reasonable number, we, nevertheless, recommend increasing the number of graduate students who can do their research at NRO in view of the unique research opportunities that the Observatory has to offer and because of anticipated future expansion of the research activity in radio astronomy in Japan. In expanding graduate education at NRO, it will be necessary, especially for master course students, to involve professors from other institutes and universities to cover other fields of research related to radio astronomy and to provide a sufficient number of supervisors. We urge the Observatory to expand such links as far as possible. To indicate the scale of the expansion required, we envision about 120 people working for the millimeter telescopes and LMSA ten years from now, supplemented by a university community of 380 researchers and students. Considering the rather isolated location of NRO, a larger dormitory for graduate students is necessary, and NRO graduate students should be given priority for scholarships to help with their living expenses. There are few facilities like NRO in the world and none in neighboring countries. It is recommended that more students be received from neighboring Asian nations. Needless to say, a good system of dormitory support and scholarships must also be provided for those foreign students whose needs are even greater than those of Japanese graduate students. Public Outreach and Education Since its establishment, the NRO has been open to the general pubic on a daily basis. Each year, 120,000 to 150,000 people visit the site where the Nobeyama staff have prepared panels and displays to explain the facilities. This open-door policy, rare among scientific institutions in Japan, is highly commended by the Committee. Most research organizations in Japan are closed to the general public, expect on special open-house days, and this has tended to reinforce the public's view that science is a closed world remote from everyday life. The Committee sincerely hopes that the Observatory's enlightened efforts to stimulate public interest in astronomy, which might be called the "Nobeyama spirit," spreads throughout the world of science in Japan. Nevertheless, several improvements could be made at Nobeyama. Some of the display panels are too difficult for the general public to understand, as can be seen from the complaints in the visitors book. The Committee recommends that the panels should be made easier to understand and more fun to read. Additional panels should be made for children. Furthermore, care should be taken not to use harsh warning notices, such as "No entry for visitors," which tend to reinforce the view that science is a closed world. Despite these criticisms, it is remarkable that the very limited and overstretched Observatory staff have managed to put up so many displays and cope with the huge influx of visitors with no special support from the government. The Committee strongly urges the Japanese government to invest in building a visitors center at Nobeyama, which should be provided with an adequate number of qualified staff to run it. It is particularly important that the Observatory should strive to reach a wider public beyond Nobeyama. Currently in Japan there is much discussion about the need for science museums to educate and interest the general public in science. Nobeyama could contribute to these efforts by providing interesting exhibits. For example, the small parabolic reflector with bouncing plastic balls on display at the Observatory helps visitors to easily understand the mechanism of radio telescopes. It would be ideal for a science museum. There is rapidly growing interest in Internet among the general public in Japan. The Observatory is preparing a home page to put on the worldwide web of the Internet. But this is intended primarily for communication with astronomers around the world. The Committee recommends that the Observatory also prepare a section on the website for the general public with regular updates of interesting information on the world of astronomy. Many schools will soon be connected to the Internet. To stimulate interest in astronomy among Japan's youth, the Observatory could actively seek out two or three schools at the elementary and junior high and senior high school levels and provide them with access to the proposed website. The school teachers and pupils could then be encouraged to interact with the site by asking questions and receiving answers from Observatory staff. This would be a useful learning process for both sides and could lead to a section for "frequently asked questions" on the website. At a later stage, the website could be accessed by schools all over Japan. As the Observatory's website for the public develops, and as other similar sites related to astronomy develop elsewhere, for example, at science museums and public observatories, they could be connected to each other and the Observatory site to give a powerful resource for education of the public about astronomy. This would not only help cultivate support for astronomy among the public, it would also help develop the spirit and culture of science within Japanese society. None of this, however, can be done without adequate staff. The present Observatory staff are overwhelmed with their existing duties, and the Committee appeals to the Japanese government to give them the support they need to meet the strong interest of the public in their Observatory.
2. Report of the Visiting Review Committee on the Division of Theoretical Astrophysics and Astronomical Data Analysis Center 18 July 1997 Visiting Review Committee Members Morimoto, Masaki Professor, Kagoshima University, Faculty of General Education [Chairman] Okamura, Sadanori Professor, the University of Tokyo, School of Science Kato, Shoji Professor, Kyoto University, School of Science Sato, Shuji Professor, Nagoya University, School of Science [Secretary] Yukawa, Tetsuyuki Professor, The Graduate University for Advanced Studies Itinerary of the Visiting Review Committee 26 December 1996 13.00 กม 18.00 Report of activities in the Division of Theoretical Astrophysics Report of activities in Astronomical Data Analysis Center Visit the super-computers and facilities 18.30 กม 20.00 Supper and talk with staff members, research assistants and graduate students 27 December 1996 10.00 กม 12.00 Report of activities in the Division of Theoretical Astrophysics, continued Explanation of the future projects and discussion 13.00 กม 15.00 Discussion for making the Committee Report 28 December 1996 and afterwards Making the Committee Report This report was written according to the following procedures. 1) According to the prearranged schedule, the purpose of the Review and then the reports of research activities and the future projects are presented to the Committee members, which were followed by questions and answers. All through the presentation, the staff and research assistants were present to make supplementary explanation and comments. 2) The Committee members visited the supercomputers and facilities of Astronomical Data Analysis Center, with explanations given by the staff followed by questions and answers. 3) During the supper taken jointly with staff members, research assistants and graduate students on the evening of 26th Dec., the Committee members had a good chance to make free talks with graduate students and obtained reference material on the graduate education in the Division of Theoretical Astrophysics. 4) Following the guideline agreed by all Committee members, Sato (Secretary) and Okamura made a draft report, and then all members revised it to make the final report. Summary of the Report 1. In spite of small number of staff members and research assistants, they have been making active researches and systematic education. 2. Approaches to observational astronomy have been attempted with excellent results appearing. 3. High level of the present activities in research and education should be maintained. As an obligatory role of the theoretical astrophysics group in the Inter-University Research Institute increasing responsibility for such service activities as constructing databases, data-archive and net-works for computers and communications is expected. 4. Future plan to establish Division of Theoretical Astrophysics and Computer Sciences which consists of 6 Research Sections and the Astronomical Data Analysis Center sounds reasonable in conception and size. However, the purpose of a few research sections and organizational relationship between research sections and the Astronomical Data Analysis Center must be exposed to further careful review. * In The Phase-II Development Plan of NAOJ dated May 1997, the Division of Theoretical Astrophysics and Computer Sciences in the previous version is divided into the two groups, one being the Division consisting of theoretical cosmic physics, theoretical astrophysics, celestial mechanics and numerical simulations, and the other being the reorganized Computer and Data Center consisting of the present Center with two new sections added. I. Research Activities Division of Theoretical Astrophysics Theoretical researchers must in general be guaranteed for free and flexible activities, according to their individuality and interest. During the eight years since the establishment of NAOJ, the theoretical group there, consisting of people with different expertises and interests, has been making researches in the wide field of astronomy (star and planet formation / element synthesis and chemical evolution in the Universe / celestial mechanics / solar physics / compact objects' magnetospheres, etc.), seeking for collaboration with observational groups in NAOJ and theoreticians outside. Making full use of the most favorable condition of their offices being next door to observatories, theoreticians positively joined in observational plans and achieved good results in the field close to observations. The group in the field of star and planet formation is competing with similar groups in the world at the frontiers of the field. They have elucidated the process of fragmentation of molecular clouds from the initial filamentary structures to later spherical collapses based on extensive numerical simulations. The group, who started from nuclear physics and elementary particle physics and is attempting to clarify the element synthesis and chemical evolution in the Universe, has strong influences upon and is re-activating the field of stellar spectroscopy that used to be the main stream in the Japanese astronomy. The Solar X-ray satellite Yohkoh has been supported by the Solar Physics group in the NAOJ, and the group in the Division of Theoretical Astrophysics is now opening new frontiers in gamma-ray and particle astrophysics using the data from Yohkoh. The Committee got clear impression that acceleration and deceleration of high-energy particles in the Sun are developing into a new field which involves not only protons and mesons but also p0 mesons and the solar Li problem. The group of celestial mechanics, a traditional field, is now extending the range of application of three-body problem, which was limited so far to the solar system, to new phenomena such as triple-star systems and the accretion discs around them. This is a promising approach to the new understanding of astrophysical phenomena. The results on magnetospheres of compact objects and black hole thermodynamics are unique. Overviewing the research activities in the past eight years, the Committee recognizes sincere attitude of the staff toward getting wide variety of objects and phenomena into perspective. Mobility of staff and young research fellow is high, and three staff members have moved to universities (Takahara, F.,*1 Ikeuchi, S. and Umemura, M.). The research field has also changed with the change of staff. Such occasional change of the field in the Division of Theoretical astrophysics should be positively evaluated. Astronomical Data Analysis Center (ADAC) Since its start, the Astronomical Data Analysis Center (ADAC) has been maintaining large computers and many work stations to give service to users inside and outside the NAOJ, and providing university users with a various kind of supporting activities. It has also been supporting JAIPA's*1 activities. These activities of ADAC have been a research basis of researchers belonging to rather small institutes, especially in the period just after the start when people were short of available work stations and software for data reduction. Taking into account the quite small number of ADAC's staff members, the Committee regards the activities as of high level, but simultaneously notes that this has been accomplished at the sacrifice of research time of members. As one of the centers of astronomical data in the world, ADAC is engaged in collection, maintenance and public service of catalogues, and the number of catalogues now collected amounts to about one thousand. Now ADAC is involved in constructing and operating MOKA (Mitaka-Okayama-Kiso Archive), and accumulating technology and experience for constructing database of much larger scale in the future. Collaborating with the Division of Theoretical Astrophysics, ADAC set up the electronic network of connecting each campus of NAOJ and also the network within the Mitaka Campus. This activity culminated to a high-level network called the KTnet in 1995. A system of supercomputers was introduced in the Heisei 8th (1996), and 50 proposals requiring long machine time were accepted in the first year. Now first scientific results are coming from the proposals. It is a common bad practice seen in many research institutes in Japan that researchers themselves must be responsible for services and maintenance of machines. This bad practice in ADAC has become mitigated since the beginning of this year. ADAC has finally come to a point where staff can spend some time to constructing data archives and databases, which are scientific work they are supposed to do. II. Research collaborations with other fields in NAOJ and with astronomers outside NAOJ Division of Theoretical Astrophysics Research staff has made use of the "ti-no-ri" (advantage of location) to collaborate with research groups in other fields in NAOJ in a variety of form and to stimulate each other. In the research of star and planet formations, one staff member has become a PI of the observational research project based on cosmic radio observations, pursued a connection between theory and observation, and obtained specific results. This is highly evaluated as a new style of research in Japan. Also, suggestions and participation of the staff to the Subaru Project have given stimulus to the people promoting the Subaru project. In particular, they are providing science drivers in the development of HDS (High Dispersion Spectrograph). The research of acceleration of high energy particles by observing solar g-ray with the Yohkoh satellite has given a fresh surprise. A fruitful area of research remains to theoreticians who are not directly participating in hardware development. The people in an orthodox and traditional field of celestial mechanics is groping for a new way of applications in astronomy. If looked carefully from a contemporary point of view, this field seems to possess possibility of unexpected growth in the near future. Division has set up places of research exchanges for the people inside and outside NAOJ through the RironKon*1 and the Yukawa Institute for Fundamental Physics, Kyoto University. Also, Division organizes several research meetings each year, to provide researchers in Japan with the chances of communication. Astronomical Data Analysis Center Introduction of a set of super-computers in ADAC has again activated big projects of numerical simulations and, in addition, enabled a variety of computing services including theoretical computation. In particular, we appreciate the following five points and expect further enhancement: 1. Financial support for big numerical computations More powerful machines in the same series as in the NAOJ super-computer VPP300 have been installed in Kyoto and Nagoya Universities and in computer centers of some other universities, but use of these machines is charged. This is heavy burdens on users. ADAC admits free use of 200 -- 400 hours of machine time per research task. This is recognized as of high astronomical value. It is highly appreciated that NAOJ has given such opportunities for theoretical researchers including graduate students. 24-hour operation of the machine is worthy of special mention. 2. Hardware and software ADAC is now equipped with hardware and software such as work stations for data analysis (SGI), high-quality color printers, the equipment to make videos, the software for three-dimensional image-analysis. The Committee highly rates ADAC's style of opening these expensive machines to public use of astronomers. These machines are too expensive to be purchased by small institutes. They also require substantial labor of researchers (manpower) to be kept in good condition. Maintaining the high-level services for users in future is highly appreciated. 3. Rental of workstations It is planned in Heisei 9th to rent workstations for universities cooperative to NAOJ. Good results are expected, to come out by this service. 4. Construction of astronomical database (http://adac.nao.ac.jp) It is a great contribution to astronomy to prepare data catalogues and to open them to public use. "MOKA" is the first of such projects in Japan that make collection of astronomical images available to the community. Further extension of such work is desirable, since this field becomes more and more important. Construction of a mirror cite of electronic versions of overseas main journals such as ApJ, A&A and MN is strongly requested. In these several years main journals have begun to publish their electronic versions, thereby providing latest information. However, the time slot to make use of them is limited in practice because of narrow bandwidth of the network lines to overseas, and hence a mirror-site set up in Japan would be very beneficial. 5. Enhancement of overseas lines. With respect to construction of the Subaru telescope, the Committee strongly supports improvement and expansion of communication line between Mitaka and Hawaii. Such expansion of the internet lines will be a large contribution to even outside the astronomical community. III. Graduate Education The staff in the Division of Theoretical Astrophysics has been giving graduate students of The Graduate University for Advanced Studies and the University of Tokyo seminars in a variety of form in such fields as solar celestial mechanics, star/planet formation, high energy physics, cosmical physics, and so on. For theoreticians, daily conversations and debates are of significant elements of research, and hence space/time is indispensable. The problem, common to many research institutes in Japan, is extreme shortage of space for discussion, and this is seriously true in NAOJ. Too small offices of research and shortage of the seminar rooms must be resolved without delay. Offices and seminar rooms must at once be increased in number, for example by building prefab houses. IV. Toward the Future For the development of this field, a plan is formulated that a new Division of Theoretical Astrophysics and Computational Sciences consists of six sections, establishing such three new sections as simulation astronomy, astro-computational science and astro-information science, and also removing celestial mechanics from the Division of Astrometry and Celestial Mechanics, in addition to the present theoretical sections (theoretical cosmic physics and theoretical astrophysics). Three sections, i.e. theoretical cosmic physics, theoretical astrophysics and simulation astronomy would be of reasonable size in the field of Theoretical Astrophysics in NAOJ. Specific contents of research may well be determined by personality and interest of each staff, and also movability of staff members must be encouraged. In particular, the posts of guest research section must be increased in number. Union of celestial mechanics and theoretical astrophysics will be expected to be mutually stimulating to these two fields. The Committee considers that the direction of astro-computational sciences must be submitted to careful scrutiny. Development of GRAPE and FX Correlators so far made and their scientific results are highly evaluated by the inside and outside of this country, and the Committee recognizes these as a fact with one consent. However, the Committee had an exciting time of discussion on how to promote development of "mono" (machine) hereafter in NAOJ. There is one opinion that it is due to having been free from "mono" that the Division of Theoretical Astrophysics could enjoy running lightly so far. The other opinion says that time is changing with the advent of necessity of "mono" = computers in many theoretical fields. There was a success in developing GRAPE and FX in the community of theoretical astrophysics, and since then it can be seen that there is a tendency that theoreticians by themselves should not only develop algorithms but also launch into development of hardware. There was then an opinion in the Committee that computational sciences in NAOJ should be positively encouraged in this direction as its characteristics, whereas there was such an opposing opinion that how effective could be the development of special-purpose computers for solving the fluid + radiative transport problem beyond the GRAPE, and the cost performance must be checked for developing a much more complicated hardware than GRAPE by themselves. In each step of advance of computational technology, e.g. the SPH-chips now under development, strategy judgment must be done properly. As a new style of astronomical observations in the 21st century there would appear observers that are based upon databases/data archives. They would not by themselves be engaged in observations, but just use the data made open for public use. Establishment of astro-information science would be of high expectation in providing a basis for such a line of investigation. The Committee recognizes the importance of making a first step forward such direction. The Committee must at the same time point out that quite big investments must be done in both human and material sides. Foreseeing that database/data archive and numerical simulation increase further and further in significance in the future, the Committee must say that the "battle array" in ADAC is too poor to achieve the above task, and ADAC should be fulfilled and strengthened in staff members. Now the time is coming when large amount data are accumulating world-widely and anyone from anywhere can make access to data, to research astronomy. In such time NAOJ possesses and are possessing big observational equipment of the first-class quality in the world, such as the group of radio telescopes in Nobeyama, VSOP, VERA and LMSA, and should take the responsibility to set up the system of providing to users data which are and will be produced by these large telescopes. By doing this, the time will come that all researchers can "observe" not only by operating large equipment by themselves, but also by making access to databases. It would be one of important roles of NAOJ as a common-user facility to enlarge the bottom of astronomy, and the Committee expects that ADAC will play a central role there. From the view-point of strengthening ADAC for astro-information and analyses, the Committee recommends that ADAC have the three sections, i.e. simulation astronomy, astro-computational science and astro-information science to belong to ADAC, and thereby make the character of a "researching center" clear. V. Summary 1. In spite of small number of staff members and research fellow, they have been making active researches and systematic education. 2. Approaches to observational astronomy have been attempted with excellent results appearing. 3. High level of the present activities in research and education should be maintained. As an obligatory role of the theoretical astrophysics group in the Inter-University Research Institute increasing responsibility for such service activities as constructing databases, data-archive and net-works for computers and communications is expected. 4. Future plan to establish Division of Theoretical Astrophysics and Computer Sciences which consists of 6 Research sections and the Astronomical Data Analysis Center sounds reasonable in conception and size. However, the purpose of a few research sections and organizational relationship between research sections and ADAC must be exposed to further careful review.* * The Phase-II Development Plan of NAOJ dated May, Heisei 9th, the Division of Theoretical Astrophysics and Computer Sciences in the previous version is divided into the two groups, one being the Division consisting of theoretical cosmic physics, theoretical astrophysics, celestial mechanics and numerical simulations, and the other being the reorganized Astronomical Data Analysis Center consisting of the present Center with two new sections added.
3. NAOJ Visiting Review Program: Report of Review for the Division of Astrometry and Celestial Mechanics, the Division of Earth Rotation and Related Fields Members of the Visiting Review Committee: Professor Jiro Arafune: The University of Tokyo Professor Satoru Ikeuchi: The Osaka University (Chair) Professor Hajime Inoue: The Institute for Space and Aeronautics Sciences Professor Toshihiro Omodaka: The Kagoshima University Doctor Yoshio Kubo: The Japan Hydrographic Department Professor Mineo Kumazawa: The Nagoya University Professor Makoto Tosa: The Tohoku University The visiting review committee, receiving reports during two days, February 25 and 26, 1997, concerning the research activities and future plans of both the Division of Astrometry and Celestial Mechanics and the Division of Earth Rotation, as well as their related fields, interchanged views among the committee members. The points of the review to which the committee paid special attention, in addition to the achievements hitherto made in research, observation, and instrumental and engineering development are as follows. With respect to the Division of Earth Rotation and the Mizusawa Astrogeodynamics Observatory: (1) Pertinence of the future plans of both the structural reorganization and the facility and research projects; in particular their fundamental lines, time scales, and reasonable sizes. (2) Anticipated effectiveness of the planned structural merger with the Division of Radio Astronomy. With respect to the Division of Astrometry and Celestial Mechanics: (1) Scientific reasoning and implementation scheme of the ongoing gravitational wave detector and the optical/infrared interferometer, as well as the future space astrometry plan. (2) Pertinence of the planned structural reorganization; in particular mergers into both the Division of Optical and Infrared Astronomy and the Division of Theoretical Astrophysics. First, the committee appreciates that the reorganization of the present NAOJ has positively affected the activities in research, observation, and instrumental and engineering development of both divisions. Consequently, there has been remarkable progress in consolidating research systems, defining research objectives, fostering volition for pioneering new disciplines, and making research achievements. The committee offers its sincere gratitude for the efforts hitherto made by both divisions. Following are the areas in which the committee recommends that both divisions make further efforts. With respect to the Division of Earth Rotation inclusive of the Mizusawa Astrogeodynamics Observatory, the committee recommends the following: (1) Clearer definitions of scientific targets for general scientific strategy and geophysical research such as, the structural reorganization of the research system and the deployment of superconducting gravimeters and, in particular, setting-up of geophysical research themes characteristic of the scheme of the NAOJ. (2) Placing more emphasis on scientific aspects than on measurement. Although the committee fully recognizes the importance of measurement, the report appears to be overly oriented to measurement. With respect to the Division of Astrometry and Celestial Mechanics, the committee makes the following recommendations: (1) Pinpoint targets among the abundant future projects, in consideration of the limited resources (particularly researchers). Especially, the committee recommends the devising of effective and innovative directions with regard to the future of positional astronomy and its line of development. (2) Innovate new stances of scientific cooperation. For example, explore the relation of the VERA project to positional astronomy and that of gravitational wave astronomy to geophysical implications. The committee recommends that both divisions prepare concrete views for the above recommendations. Although the committee recognizes that the future is not clearly visible, following are general views of the committee with respect to future plans for research and development, as well as for the structural reorganization: (1) VERA is a project to be urgently promoted. It is recommended that its supporting communities be broadened by more clearly defining attractive scientific targets and by seeking possibilities by which as many researchers as possible among university and college, as well as young researchers, can join the project. (2) With respect to the ongoing development of an optical-infrared interferometer, which is anticipated in future worldwide development, the committee considers it important to begin by clearly defining strategic objectives and by fully exploring technological and scientific perspectives. Hence, the committee recommends the full elaboration of the structural reorganization plan to merge the Gravitational Wave Astronomy Section and the related sections of the Division of Optical and Infrared Astronomy into the Division of Advanced Astrometry and Interferometry, in view of post-SUBARU strategy for optical and infrared astronomy. (3) The committee considers it essential for future positional astronomy to promote it in galactic-scale with reference to distant quasars in the light of the outcomes produced by HIPPARCOS. To do so, the committee, considering that the most convenient and highly promising way is the space astrometry, recommends that the group give serious consideration to its implementation. Among a diversity of difficulties to be overcome at present, the committee particularly emphasizes the necessity of a powerful project leader in addition to technological development. (4) The committee recommends that the merger plan of the VLBI involve sections of both the Radio Astronomy Division and the Division of Earth Rotation continue to be elaborated and be gradually materialized according to maturity independent of the climate of the VERA and RISE projects. The committee also recommends that the community increase efforts to set up wide-scoped and clear scientific targets for astrophysics, astronomy, and Earth-planet sciences inclusive of the RISE project. Further review of the Mizusawa Astrogeodynamics Observatory should be particularly required. (5) The committee considers that the planned merger of the Galactic Dynamics Section and the Celestial Mechanics Section of the Division of Astrometry and Celestial Mechanics into the Division of Theoretical Astrophysics will produce positive effects by handling extensive celestial objects ranging from planetary to cosmic scales and by developing common research techniques. However, it is indispensable to foster a practical system which eases communication among researchers and research cooperations among young researchers and graduate students. (6) The committee considers that it is important for gravitational wave astronomy to systematize a research scheme for enhancing the technological potential of the Japanese group and thereby to conduct instrumental and engineering development. Over the long term, the investigation should be promoted in full collaboration with other institutions. In conclusion, stated above are main issues of the discussions held in the review committee. It is recognized that for the most part the structural reorganization to the present NAOJ has come to fruition. On the other hand, there still remains several unattended aspects to be revamped. Hence the committee strongly expects both Divisions to make further efforts for implementing the future projects by more explicitly defining their scientific targets. In addition, positional astronomy, celestial mechanics, and Earth rotation are scientific fields which (often) do not tend to attract the general public's interest. In order to achieve scientific development in these fields, the committee recommends that efforts be made to awaken wide interest within the general public by, for example, publishing enlightening books and articles in general scientific magazines about the implications of the outcomes of these fundamental fields for the human understanding of the universe. On the Present Status of the Division of Astrometry and Celestial Mechanics and the Division of Earth Rotation (Summarized by Chair: Satoru Ikeuchi) Both divisions have conducted theoretical and observational research as a basis of defining and realizing the celestial reference system and determining the Earth's variable rotation, which are the most fundamental requirements for astronomy. Recently, however, as a result of tremendous expansion of the front of astronomical research and innovation of research facilities, it has become necessary to expand beyond the classical research techniques and to broaden research objectives. Both divisions, set up by the inauguration of the NAOJ, have intended to innovate the research fields by introducing new aspects of research systems. Currently, both divisions are still making effort toward modernization and systematization of the research systems and are making future plans for further development of the fields. Following are the resumes of the present status of both divisions. [The Division of Astrometry and Celestial Mechanics] (1) By means of observations of motions of the Sun, planets and satellites with the use of the photoelectric meridian circle, and precise positioning of the solar system objects and faint stars, studies to realize ideal inertial frame were conducted by dividing apparent rotation and deformation of the celestial reference frame into motions of the Solar System, fixed stars, and Our Galaxy, respectively. (2) In cooperation with other groups, development of the optical and near-infrared interferometer is ongoing for the purpose of realizing 1 mill arcsecond level high-resolution observation, and white light fringe has been detected by laboratory experiments. Development of 4-m single baseline interferometer is also ongoing. (3) Studies of galactic dynamics have been conducted, such as, dynamics of the galactic disk by means of analysis of spatial motions of M-K type giant stars, development of astrometric techniques for determining masses of MACHO, and the chemical and dynamical evolution of galaxies. (4) Studies of celestial mechanics, by means of precise analysis of the Solar System objects have been made, such as, long-term motion of the Kuiper belt objects, dynamical evolution of the nine planets in a 450 million year scale, and relation of secular resonance and the number of planets at the time of formation of the Solar System. (5) Manufacturing of the 20m laser interferometer including experiments for its stable functioning and construction of the 300m laser interferometer (TAMA300) have taken place. (6) Conversion formulae among various time systems were developed on the basis of general relativity, and unit conversion coefficients of primary astronomical constants were determined with high accuracy. [The Division of Earth Rotation] (1) Development of highly stable functioning mechanism of the 10-m radio telescope was made and its efficiency was evaluated by means of observations with the domestic VLBI network. As a VLBI station at Mizusawa, maser source observations, geodetic and Earth rotation observations have been conducted, and the observations were correlated at the correlation center at Mizusawa. Provisional experiments, system designing and site selection for VERA Project, fundamental experiments for RISE Project, and high precision experiments for phase referencing relative VLBI were made, and thus the research group related to VLBI sciences has been consolidated and research and development for future plans have been promoted. (2) Based on continuous measurement by means of a superconducting gravimeter at the Syowa station of the Antarctic, gravity changes due to short periodic and long periodic Earth tides, and the polar motion were analyzed and the ocean tides coefficients were improved. Based on development of an absolute gravimeter of rotating vacuum pipe type and its continuous record, effects of ocean tides loading and liquid-core resonance were detected. (3) By means of continuous measurements by both nation-wide GPS and crustal deformation at Mizusawa, processes of seismic energy release of Sanriku Far Off-Shore Earthquakes occurring on July, 1992 and December, 1994 were monitored, and demonstrated various types of crustal deformation, such as, silent or slow earthquakes. (4) Based on analysis of meteorological data produced by the Japan Meteorological Agency and Earth rotation data produced by space geodetic techniques, studies of the relation between atmospheric angular momentum variation and the Chandler wobble have been conducted
4. The Solar Research Groups of the NAOJ: Report of the Visiting Review Committee Committee members: Hiroki Kurokawa, Susumu Kokubun, Hiroto Tabara (chair), Toshio Terasawa, and Fumiaki Makino 1. Research Results Through their major projects (Yohkoh and the Nobeyama Radioheliograph), it is generally agreed that the solar research groups*1 of the National Astronomical Observatory (NAOJ) have attained international leadership in the study of active phenomena in the solar corona. The new discoveries resulting from Yohkoh observations of flare energy release mechanisms, high-energy particle acceleration, and coronal heating are especially noteworthy. Among all Yohkoh has revealed the dynamic variability of the solar corona, including dynamics of magnetic fields during active phenomena such as flares, and has established a scenario for the magnetic reconnection process. These results have contributed to activate solar physics research throughout the world. They also have impacted broader research areas of magnetic activity in stellar and galactic plasmas, solar-terrestrial environment, plasma fusion, and so on. The Nobeyama Radioheliograph is giving results on the acceleration of non-thermal electrons in flares via synchrotron radiation from them and also on the behavior of plasmas via thermal plasma emission. There are major results from data coordinated with soft X-ray and optical observations of flare particle acceleration and prominence motions. Still there are many unresolved points regarding the mechanisms of non-thermal particle acceleration, and we look forward to results from observations coordinated with Yohkoh in the coming rise phase of solar activity. The ground-based optical observations include the fundamental vector magnetograph observations from Mitaka and the CCD spectroheliographic observations from the Norikura Solar Observatory, which are continuing step by step to produce research results. We also anticipate direct observations of the coronal magnetic field from the liquid-crystal-based polarimeter recently completed at Norikura. Interpretations of Yohkoh observations by large-scale computer simulations are fundamentally important, and the vigorous development of this research work has been achieved by the solar research groups of NAOJ. Jet and flare simulations, in comparison with soft X-ray observations, lead to the establishment of models based on magnetic reconnection. We note that the results also apply to accretion disks around stars, and to jets and coronae of active galaxies. Heretofore applied only in these areas, one suspects that variants can also be applied to X-ray stars and galaxy-cluster plasmas. We should point out that the solar research groups of NAOJ have successfully built the foundations for space observations, while continuously pursuing ground-based optical and radio observations and at the same time obtaining major results from satellite X-ray observations. Japan has thus maintained its world leadership in solar observation across the range of wavelengths including X-ray, radio, and optical observations, and the Japanese researchers in solar physics are in the process of reaching an unrivaled crest of activity. 2. The Structure of Future Projects i) The SOLAR-B Satellite Project The realization of SOLAR-B is planned to drive research on the Sun and cosmic plasmas. It is an appropriate project considering the existing research results in the context of the major Hinotori and Yohkoh programs. There is an international expectation that important elements of SOLAR-B will be achieved and will relate to the fundamental solar-physics problems of coronal heating and how the photospheric magnetic flux elements combine to supply energy for coronal phenomena. The planned SOLAR-B payload consists of a visible-light telescope (for magnetic fields), an X-ray telescope, and an XUV spectroheliograph. The U.S. group that managed the Spacelab and SOHO instruments is indispensable for the international development of the principal instrument, the optical telescope/magnetograph. It is necessary to accelerate the ongoing preparation for the instrument development of this key payload element as well as establishing a framework of international collaboration. We remark on areas in which the preparation is not complete and for which NAOJ and other responsible institutions for the SOLAR-B must make technical explorations. It will be necessary for the solar research groups of NAOJ to strengthen the instrument development, as well as to realize the needed structure in collaboration with other solar-research-related organizations than NAOJ. ii) The Norikura Solar Observatory Considering Norikura in the post-2002 time range, NAOJ has made a positive proposal to convert it into a section in a "Advanced Technology Center" and the ground-based facilities at Mitaka. With the objective of a reorganization towards a powerful broad capability for space astronomy, there are not a few things that must be studied with respect to the practical consequences of such a move. One example is doubt about the broad inefficiency of the plan involving the labor of annual winter closures of the observatory, with additional effort for spring openings. The cooperation of the staff has resulted in fifty years of accident-free operation under difficult conditions. Because of such a history, the opinions of the staff must be thoroughly and prudently investigated before considering the closure of a place such as the Norikura Solar Observatory, or to plan to convert it into another organization; however considering the Phase-II Development Plan of NAOJ, a concept firmly based on the observatory's research trends, may make it inevitable to close it down. However bearing in mind that ground-based observations (by comparison with space observations) have the advantage of low-risk instrument development, and of continuing routine observations with the aid of automation, currently successful research areas must be continued up to the maximum limits of their progress; it will be necessary to maintain the observatory as long as there are enterprising scientists or important research topics. iii) The Nobeyama Radioheliograph A plan has been presented whereby a part of the Nobeyama solar radio group would join the cosmic radio research group, following the results gained from the next activity maximum. We note the difficulties of long-term maintenance and operations and of the development of a new interferometer. From the point of view of efficiency, it would be reasonable to observe an interval of one and a half solar activity cycles to complete the originally intended research activity. However it seems probable that the objectives of solar radio observations will not fully be met by then. Especially given the SOLAR-B plan for one-arcsec soft X-ray observations, the realization of a similar arcsec-resolution capability at radio wavelengths will require a discussion of the pros and cons of whether our country should develop a more advanced radio-wave technology for the study of magnetic coronal heating mechanisms, such as microflares, and for the study of high-energy particle acceleration mechanisms. iv) Ground-based Observations Recently developed observing instruments at Mitaka are being maintained for an interval, considering the power of their observational objectives and actual applications. Ground-based observations have advantages that are complementary to space optical observations, and also may serve as a foundation for space observations, but one has the impression that no detailed and specific planning has been made. It is necessary to study which instruments in the facilities to maintain, to terminate, or to transfer. In our country "space weather forecast" is one of the on-going projects of the Communications Research Laboratory of the Ministry of Posts and Telecommunications who is in charge of radio alerts. In the Phase-II Development Plan of NAOJ, the synoptic observations such as for monitoring the solar surface for a long time are planned to be conducted in a labor-saving way with emphasis on themes that are not achieved by satellite observations. We note that the ongoing development of space will continue to require deeper information about the Sun, which controls the near-Earth environment; thus it is of crucial importance to maintain ground-based observation facilities under a good coordination with other organizations. Space observations provide capability for research topics requiring spatial resolution or continuous observation, and will clarify a variety of research problems in solar physics, but the significance of ground-based optical observations remains unchanged. We note that it goes without saying that regular ground-based optical observations lay the foundation for scientific programs in space, as well as in the development of instrumentation and experiments. 3. Joint Research and Open Use The achievements of Yohkoh stand out as an example of successful results through cooperation between observational and theoretical teams, and we thus hope that these groups will continue in this manner. On the other hand their success seems to have resulted within a rather Japanese style of total utilization of manpower, where even theorists have been engaged in spacecraft operations. We might say that the Yohkoh situation is not unique in that every scientific achievement in Japan has been backed up by such a system of total manpower mobilization. In this sense there remains a question as to whether we should depend on such a system when we look into our research prospects into the twenty-first century. From now wouldn't it be necessary to build a system which will ensure enough manpower as well as the material support? We think one of the key elements behind the Yohkoh success is the system by which we made our data open in a broad framework, to the international community. The Yohkoh achievements have also greatly stimulated research in the heliosphere and terrestrial magnetosphere. We would like to commend highly the people involved in this project for their time and effort for actively advancing systematic and efficient data utilization and joint research. Despite the assessment above, some persons are concerned that the utilization rate of the data is not sufficiently high. Shouldn't we process our data into a more accessible data base before making them open? The same can be said about the optical observations and the Radioheliograph. This is a problem we must consider in the transfer and improvement program for the "Astronomical Data Center" which is included in the Phase-II Development Plan of NAOJ. To improve the research level of the Radioheliograph, one must try to enlarge and enrich the joint research environment. The record of past joint research projects shows a steady level of topics each year, but it concerns us somewhat that we do not find many research subjects led by Japanese scientists. We understand that efforts are being made to promote the further utilization of the data and to conduct workshops to facilitate the use of these data, but we believe that further measures are necessary to stimulate the data usage. 4. Research Structure and Personnel In the solar research environment the appropriate personnel arrangement poses a difficult question. The number of research assistants (with permanent posts) in this field is five, including radio astronomy, and this is certainly too few when we realize that these researchers should be responsible for cutting-edge observations as well as related equipment development. We believe that in the field of observational research good original results do not come without the researcher actually working with the telescope. In this sense promoting various projects such as SOLAR-B and the coronal magnetic field measurements at the Norikura Solar Observatory require an immediate increase in the number of research assistants. In the case of a satellite observation, one expects immediate results once the observatory gets to orbit. For this reason the major efforts on the part of the esearchers would go to data analysis on a five-to-ten year time scale. Consequently only a limited number of researchers actually get to do basic instrumental development. In a satellite project where the time scale is ten years, in the anticipation for the next mission, one must consider the balance among various activities -- the basic development of new equipment toward the next mission, the handling of the observed data in progress, the distribution of data to the wider scientific community, and the research based on the observations -- and the personnel who participate in them. For the promotion of a satellite program three or four sections in NAOJ are not enough, and the systematization of the project including the related organization is inevitable. A glance at the personnel at the NAOJ shows that the number of the technical staff members is large compared with that of the research staff. This is an advantage not shared by other research facilities in Japan, though one cannot claim that the number of specialty technicians is large when compared with research centers in Europe and the U.S. In the case of a satellite project, large parts of the instrumentation will be subcontracted to manufacturers, and thus the opportunity for technical staff to be involved becomes smaller. At this point we note an alternative opinion disapproving of the trend towards a major role for satellite projects. We believe that future research will gravitate further towards technical development. Accordingly the position of the technical staff will become more important. Under this circumstance we have an urgent need to reassess the roles of our technicians and how we treat them. In order to help a technical staff member apply his ability in his research environment, good foresight at time of employment and appropriate guidance by professor after employment are necessary. The Phase-II Development Plan of NAOJ contains a "Advanced Technology Center" and an "Computer and Data Center". When (and if) this transfer of systems takes place we hope that the authorities will deal with a new placement of technical employees with consideration of their function in supporting satellite projects. Graduate Education The past two years have produced five doctoral degrees and eight master's degrees. The number is not particularly large, but with respect to the number of fields related to solar research and the scale of our astronomy departments it is a reasonable figure. The persons obtaining master's degrees are spread over many different organizations; this is a notable educational accomplishment of the NAOJ. From some graduate students one obtained the opinion "Even though I intended to pursue theoretical research in graduate school, I was recruited by the Yohkoh group to engage in spacecraft operations with no previous knowledge. Now I can understand them." When a graduate student participates in operations there is an educational plus in that he obtains access to the newest data; he can also prepare to apply his experience of satellite observations to the next satellite project. However there are some graduate students who do find working with spacecraft operations to be a burden. This poses a problem whose pros and cons should be discussed when we consider the system of operations for new satellite projects.
5. Report of the Visiting Review Committee on the Optical and Infrared Astronomy Facilities, NAOJ The Division of Optical and Infrared Astronomy Research is consisted of; Division of Optical and Infrared Astronomy Subaru Telescope Hawaii Facility Okayama Astrophysical Observatory Dodaira Astronomical Observatory Advanced Technology Center 1. Introduction On the occasion that almost ten years have passed since the National Astronomical Observatory of Japan (NAOJ) started as an inter-university joint research institute, a Visiting Review Committee has been formed to summarize its past scientific activities and to reflect the results on its future plan. This report presents the outline of discussions in the Visiting Review Committee on the Division of Optical and Infrared Astronomy Research, held on the 22nd and 23rd of April, 1997. Extensive and detailed reports had been delivered to the committee members in advance. After the presentations by the people in charge, the Review Committee had a question-and-answer session. The Committee members also made a tour of the Advanced Technology Center. This report summarizes the past activities, analyzes the present activities, and gives a guideline for future developments. The member of external reviewers are Chief Reviewer Prof. Haruyuki OKUDA Institute of Space and Astronautical Science, Division of Space Science Reviewer Prof. Dai'ichiro SUGIMOTO University of Air Department of General Education Prof. Tuneyoshi KAMAE the University of Tokyo, School of Science Department of Physics Prof. Humio TAKAHARA Metropolitan University, School of Science Department of Physics Prof. Ken'ichi WAKAMATU University of Gifu, Faculty of Technology Department of Civil Engineering 2. Activities in the Division of Optical and Infrared Astronomy 1) Research Activities using existing facilities In this field, observational research works have been performed mainly with the telescopes at Okayama Astrophysical Observatory (OAO), at Kiso Observatory, and at Dodaira Astronomical Observatory (DAO). OAO was founded in 1960 and its 188-cm telescope was then of prominent size in the world, and played an important and basic role in initiating astrophysical research in Japan. For example, research studies in stellar astrophysics, like the classification of A-type peculiar stars and carbon stars, had international reputation. But it is regretful that OAO gradually recessed from the scientific frontier, because of the poor sky conditions (clear night rate, seeing, and bright city light) and the delays in replacement into a larger telescope and in the development of modern instruments. Meanwhile, the leading groups in the world were entering into an era of competitive construction of large telescopes (3 to 4m in aperture), developing more efficient and powerful instruments with new technologies. In contrast, Japanese astronomers had rather limited collaboration with relevant research fields like physics and sensor technology that resulted in a delay in development of these new frontiers. In 1988, a new movement was undertaken in the form of the reorganization of Tokyo Astronomical Observatory, an affiliate institute to the University of Tokyo, into an inter-university joint research institute renamed as National Astronomical Observatory of Japan (NAOJ). In the research field subject to this review, a new organization of the Division of Optical and Infrared Astronomy was formed. This division includes both fields of infrared and optical astronomical research. At the same time, the rather independent management style of each research section was shifted to a more efficient and cooperative management of the Division. This has become a driving force to open new research and development fields. For example, the introduction of new techniques such as CCD cameras and the development of various infrared cameras and spectrographs like OASIS (Okayama Astrophysical System for Infrared Imaging and Spectroscopy) have improved the situation substantially and activated research and development (R and D) works in many other fields. They have resulted in the successes of many interesting observations such as Shoemaker-Levy comet impact on Jupiter and spectroscopic studies of QSO's in infrared, which are internationally appreciated. Dodaira Astronomical Observatory (DAO) was founded in 1965, taking into account its proximity to the Headquarters at Mitaka, Tokyo. It has been effectively used for observations of unpredictable phenomena like comets and novae as well as constant monitoring of variables stars. Polarimetric observations were extensively made by a unique photo-polarimeter. But regrettably, owing to the effects of the city light of Tokyo, the potential observational power cannot be fully used. However, DAO's role in astronomical training of graduate students and testing of instrument development is still valuable. In fact, a new management system for effective telescope utilization is being investigated, including direct management by a users-group from multiple universities. 2) Subaru Project Because of the poor observational conditions, the productivity in optical and infrared astronomy in Japan is limited, and it is difficult to keep its research at a world top level. In order to overcome this situation and expecting future reform and progress in optical and infrared astronomy in Japan, the construction of a large optical and infrared telescope "Subaru" was planned and is being undertaken by NAOJ with the nation-wide support of astronomers. Subaru will be one of the largest telescope with a monolithic mirror of 8-m in diameter, first realized by the new and noble technique of active mirror control. The summit of Mauna Kea in the Island of Hawaii was selected for its construction site in order to get the best observational conditions. The full usage of the active optics together with the selection of the best site would provide the highest resolution as good as 0.1 arcsec, which is close to that attained by the Hubble Space Telescope. To realize this goal, many new ideas have been taken into the telescope design. For example, a laminar air flow control in the dome is one of the ideas, which Subaru first introduced. Such a high-tech telescope is the first to be realized by the introduction of new technologies and the active cooperation with experts in the relevant industrial and research fields. Such endeavors are also undertaken for the developments of observational instruments and electronic devices. For example, in cooperation with a group at Kyoto University, a unique instrument called OHS (OH-airglow Suppressor) is under development for Subaru, aiming at a drastic reduction of the sky background level by quenching the OH airglow emission. CIAO (Coronagraphic Imager with Adaptive Optics) developed for Subaru will be a powerful instrument for the search of extra solar planetary systems. The construction of the Subaru telescope began in 1991, and its mounting and driving structure is now being assembled in the enclosure, already completed on Mauna Kea. To reach the goal of first light in 1998, the whole process has been sped up. For the steady progress of the project, it was extremely important and useful that the basic technologies, such as active mirror control have been established through model experiments prior to the telescope construction. Seven observing instruments were selected and their development and fabrication began in 1996. In addition to OHS and CIAO, Suprime Cam (Subaru Prime Focus Camera) is an instrument with extraordinary efficiency. The common technical elements of the instruments, such as the control system of the CCD, the data acquisition system, and the adaptive optics, were developed in advance. It should be pointed out that these developments contributed a great deal to the implementation of the observation system of Subaru. These techniques have been developed in close Connection with scientific activities at OAO and Kiso Schmidt Observatory, and with international cooperation in the SDSS project. An extremely accurate and complex computer control is required for the active control system of the mirror support, the high precision telescope tracking as well as for the operation of the observational instruments and hence a large-scale system design and associated software developments are necessary. Extensive efforts are devoted to the developments of such systems, including tera-byte size data handling, as well as to the preparation of observational database system. A new idea so called "parallel analysis", as well as automatic observations, and remote operation of the telescope are also introduced to anticipate future progress. Operation of the observatory in the overseas site is a completely new experience and hence creation of a new managing and supporting system is inevitable. A ground base supporting office has been opened in Hilo, Hawaii and started its function in April 1997. Astronomers, technical staffs, and administrative staffs took offices to supervise the construction of the telescope and related facilities. 3) Advanced Technology Center The Advanced Technology Center was founded as an attached facility to promote R & D works for instrumentation of astronomical devices. This was a unique facility first realized through the strong support of the Ministry of Education. It should be emphasized that this kind of facility is inevitable to promote really creative works. In fact, in this center, the CCD camera system at OAO was developed, the technique of the adaptive optics for Subaru was established and now the basic technologies of optical interferometry is under development for future applications. The Advanced Technology Center has been equipped with many new technology machine tools with which a few but skilled technicians are working enthusiastically for the development of new observational instruments. 4) Open-use and Joint-research, and Domestic Organization OAO has been offered for open-use and joint-research by nation-wide researchers, although no official support for its running had been given before its reorganization in 1989. This has made an essential contribution to lay the foundation of astrophysics research in Japan. But, in addition to the poor weather conditions, its observational time was shared by so many researchers, that made the observations fragmented and inefficient. After the reorganization, OAO is operated as a open-use facility and officially supported. Consequently, the opinions from nation-wide researchers are more properly reflected on the allocation of the telescope time and the development of instruments. As a result, the telescope is used more effectively by a wide range researchers, including the training of the graduate students, and observations have been highly activated. In particular, developments of the observational instruments jointly made with external groups (e.g. a Cassegrain spectrometer: SNG (Spectral Nebular Graph) of Kyoto group) triggered the development of OOPS (Okayama Optical Polarimetric Spectrograph) and OASIS. These activities have also raised astronomers' interest of developing new instruments that culminated in the ambitious Subaru project. 5) International Collaboration Related to the construction of the Subaru, several symposia were held for exchanging information on large telescope projects and for discussing international collaboration in the relevant technology developments. The opportunities for astronomical observations with foreign telescopes and joint-developments of instruments, as realized by the Japan-UK collaboration, was also very useful to maintain their scientific activities before the Subaru project. The scientific interaction growing with East Asian countries is important for future collaboration in astronomy with Asian countries on a global scale. 6) Future plan Although the Subaru project is the most urgent program (the biggest task for the Division of Optical and Infrared), the post-Subaru programs are under planning in the framework of the Phase-II Development Plan of NAOJ. As an possibility, a development plan of optical and infrared interferometry is investigated with the collaboration of the Astrometry Division. The collaboration of the two groups should be encouraged to activate their research activities. Future plans like launching a large space telescope and construction of moon-base observatories are also being discussed. 3. Assessment of the activities and Survey of the problems to be solved As mentioned above, the Division of Optical and Infrared in NAOJ performs very active research works centering on the Subaru project. It is very impressive to see that all astronomers and technicians in the Division (the biggest one in NAOJ) are promoting the project with great enthusiasm and tireless efforts under a definite guide line. Nevertheless, there are some problem to be solved. Here we would like to point out these problems and to give some suggestions and advice for their improvements. 1) Overview In spite of the very limited human resources, the present research works in this Division has been promoted extensively through the Subaru project under a clear guiding principle. The Subaru project was planned purely from the viewpoint of necessity and importance of science itself and to boost up the astronomical activity of our country to the world top level. Such an approach has so far been the exception in our country, and it should be highly appreciated that such a plan will be indeed realized soon. This may have come from their confidence born in the successful construction and operation of the Nobeyama radio telescopes. The project is now at a half point, and the final evaluation should wait until first scientific results come out. But we are well convinced with its success seeing the present progress. However, it should be pointed out that the Subaru project is too big compared to the number of working staff presently involved. For this reason, the staff members have to spend most of their times on the construction of the facilities, as well as the development of the instruments at the expense of scientific researches. This is typically seen in the recent statistics of the number of their scientific papers. In order to produce unique scientific results with the Subaru telescope competing with the other groups with 8-m class telescopes, it is important to design scientific programs aiming at the forefront of astronomy, and to proceed with the development of the science instruments accordingly. 2) Research Organization As mentioned above, it is a big concern that the human resources in the Division are still poor, although recently considerably improved. Presently, the staff overcome the difficulties with their enthusiastic efforts and the supports of engineers in the industries. But this would lessen their scientific activities, and prevent them from developments of new techniques in the early stages. This is a common structural defect in the research organization of basic sciences in Japan. By substantial increase of engineers and technicians, astronomers would be able to devote their time to genuinely scientific works. In this sense, the foundation of the Advanced Technology Center was of great importance. Although many excellent works have already been done in the Center, more engineers and specialists are required to accomplish higher activity levels. While increasing the manpower, it is also important to take care of the employment of young engineers and technicians in order to keep their incentive to the new research works, and maintaining their high technical level. 3) Development of observational instruments Seven focal plane instruments are being developed for the Subaru telescope. They may be a little too many, even comparing with those of the similar foreign projects, for it is not easy to accomplish their full performances within the human resources presently available. Many instruments may be necessary to respond to variety of research works and various interests of scientists, but they should be carefully selected so that some efforts can be put to the development of next generation instruments. Under the highly competitive conditions that many 8-m class telescopes are going into operation almost at the same time, only unique instruments can produce unique sciences. For the development of such instruments, cooperation with the external groups would be very effective. 4) Data Handling and Analysis System The system for the acquisition and the analysis of observational data is now being extensively developed. However, the archiving system of observational data for general users has not been implemented; that is the most undeveloped area in the data handling system in our country. It is very important and urgent to establish such a system for efficient utilization of the enormous data produced by Subaru. This is a common problem to many other areas like radio and space observations. A common facility for all of astronomy called "the Computer and Data Center" is under consideration. 5) International Collaboration Not only the Subaru project but most astronomical activities from now on cannot proceed without international collaboration. On one hand, already many collaborations have been undertaken in various fields. The collaboration in the "8-m club" of the big telescope project teams and the joint developments of the instruments with the University of Hawaii are very successful examples. The unique idea of the enclosure for Subaru was reflected on the other 8-m class telescope designs. Contributions like these are really wanted by the international community, and such endeavors should be continued. On the other hand, international collaborations often meet various difficulties due to judicial controversies and cultural differences, but it is urgent to make legal arrangements for living and working of staff members, particularly of graduate students in Hawaii, in cooperation with Monbusho (the Ministry of Education) and other relevant Ministries. 6) Joint Research After the reorganization, the joint-research system both for astronomical observations and instrument developments has been much improved. In particular, many external researchers are successfully participating in the joint-developments of observational instruments for the Subaru project. But, comparing to NAOJ, the general research conditions in universities are still considerably poor, and this unbalance makes it difficult to make smooth personal exchange between the institute and the universities. For this reason, it is inevitable to improve the research conditions in the universities in parallel. At the same time, it is greatly appreciated for experienced researchers in NAOJ to go out to the universities and set up new astronomy groups there. For narrowing such gaps of research environments between NAOJ and the universities, it may be worth considering to transfer the facilities of OAO and DAO and their management to a cooperated organization run by multiple universities. 7) Future Plans As noted before, the Subaru project is one of the biggest projects in scale and content ever experienced in Japanese astronomical community. Therefore it should be emphasized that various problems and even some distortions may result in the future plan, if the project is continued under the current insufficient conditions. In the Phase-II Development Plan of NAOJ, the interferometry in optical and infrared regions and the observations in space are discussed. These proposals are a natural extension, but they are not easy to realize in parallel with the Subaru telescope. It is a dilemma that the concentration of manpower for bringing a big project to success, despite the unfavorable conditions, may prevent the preparatory study towards the next project. Therefore, it is important to make a careful assessment the time scale and the feasibility of the Phase-II Development Plan. Optical and infrared interferometry, a space telescope, and observatories on the Moon are all interesting projects in the future, but, it is not recommended to start them at the present technical level, and under the current organization. Developments of the basic techniques in these fields, and implementation of expert researchers should be first undertaken. 4. Summary and Recommendations The Optical and Infrared Astronomy group in NAOJ, is steadily promoting their projects by setting a clear goal to catch up with the leading countries in the world, and to place their research level at the very front of astronomy. Particularly, this group has played a central role in the promotion of the Subaru project, i.e., construction of one of the biggest optical and infrared telescopes in the world. As the result of their efforts, the Subaru project is now just before completion. The great efforts for the development of various instruments and for the foundation of the Advanced Technology Center should be highly appreciated. We would like to express our sincere respects to all of the group members for that, although they met various difficulties, they have overcome these difficulties through their constant effort and strong will. In particular, we are impressed by the enthusiasm and efforts of all related members (astronomers, technical staffs, administrative staffs, and others) towards the success of this project. It is also appreciated that NAOJ played its role as a open-use institute to support and cooperate in observations and developments of instruments with other university researchers. However, in order to complete this challenging project successfully, and to extend its future progress, we strongly recommend the following improvements or proper changes. 1) Improvements of Research Organization A drastic improvement of research organization, i.e. manpower and facility, should be undertaken urgently. This is inevitable in order to extract the full power of the Subaru telescope and to advance future works. It is particularly important to reinforce technical staffs for the support of the telescope operation and the instrument developments. Similar improvements should be also applied to the other universities to make their collaboration more effective. 2) Instrument developments More efforts should be taken for instrument developments. That is crucial to extract the full performance of the Subaru telescope. Furthermore, it is very important to implement observational techniques foreseeing future research. An extension of the present Advanced Technology Center to a more consolidated facility, "Frontier Technical Center for Astronomical Instruments" envisioned in the Phase-II Development Plan should be encouraged. 3) Consolidation and Establishment of Data Analysis System For efficient and extensive utilization of the enormous data to be produced by the Subaru telescope, a consolidated data center for data analysis and data archive should be urgently implemented. It is a good idea to realize the Astronomical Data Center proposed in the Phase-II Development Plan and to open it to general users. 4) Encouragement of Open-use Activities Nation wide and also international collaborations are strongly encouraged to draw on the enormous potential power of the Subaru telescope. To this end, it is important to develop the operational and the supporting systems in Hawaii. In particular, it is very important that the judicial and financial environments in Hawaii should be properly fixed, for example, to guarantee the travel and living expenses for graduate students considering that the activities take place in a foreign country. 5) Long term programs The future programs of optical and infrared astronomy proposed in the Phase-II Development Plan roughly follow our recommendations as described above. We hope that they will be successfully realized along those guidelines. For long term programs, such as the interferometry and space observatories, more basic investigations in technology and science should proceed prior to their initialization as real projects, considering their large scale and innovative characteristics. A more steady organization including international collaboration will be necessary for their realization. 1997. 6. 22
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