INDIAN INSTITUTE OF ASTROPHYSICS Annual Report 1989-90 Front Cover (inset) : Aerial view of IIA, Bangalore Cover photo & design : Pankaj Shah Edited by M. Parthasarathy & S. S. Hasan Produced by S. S. Hasan Printed at Vykat Prints, Bangalore-560 017 Contents Page Governing Council ....................................... ..- .......... v The Year in Review 1 Research Highlights 3 Solar Physics 5 Velocity fields 5 Chromosphere 9 Corona 9 Magnetic fields 10 Miscellaneous 14 Solar System 17 Comets 17 Asteroids 17 Planets and Satellites 18 Star/Solar system formation ................................. 19 Stellar Physics ............................................... 21 Novae and Supernovae ..................................... 21 Be Stars .................................................. 21 General 22 Supergiants 25 Star clusters 29 Radiative transfer and Scattering ............................. 30 Interstellar Medium and Planetary Nebulae ........................ 35 Pulsars 35 Symbiotic stars and Planetary nebulae ......................... 35 Galaxies, High Energy Astrophysics and Cosmology ............... 37 Galaxies 37 Quasars 38 Solar Terrestrial Physics Ionosphere . 43 Geomagnetic phenomena 45 Instrumentation 47 Computer facility .......................................... 47 CCD system .......................................... , ... 47 Data acquisition/processing system ............................ 47 System performance of the telescopes ......................... 49 Radio telescopes 49 Auxiliary instruments 50 Optics division 51 Mechanical engineering group 52 National Facilities 53 Computer software ........................................... 53 2.34 m Vainu Bappu Telescope .............................. 53 Instrumentation Cell and PDS 57 Growth of Astronomy 59 General 59 Lectures/Colloquia by visiting scientists ....................... 60 Ph.D program ... , ........ " .......... '" .................. 61 ConferenceslLectures . 61 A wardslHonours . .. 62 Library ...................... '" . " . " .... " .. " ............ 63 Staff List ................... ~ . .. .. .. .. .. .. .. .. .. .. .. .. .. .. ....... 65 Appendices .................................................. 69 Appendix A (Publications) .................................. 69 Appendix B (Miscellaneous) ........ ~ ......................................... 81 Appendix C (Observing conditions) ........................................... 83 Governing Council (for the triennial term 1988 June to 1991 June) Prof. M.G.K.Menon, FRS Chairman Honourable Minister of State for Science & Technology, Atomic Energy, Space, Electronics & Ocean Development Govt. of India, New Delhi The Secretary Member Dept. of Science & Technology, New Delhi Mr.B.K.Chaturvedi Member Joint Secretary (Finance) Dept. of Science & Technology, New Delhi Dr.K.Kasturi Rangan Member Director ISRO Satellite Centre, Bangalore Dr.N.A.Narasimham Member 18 Saras Baug, Deonar, Bombay Prof.V.Radhakrishnan Member Director, Raman Research Institute, Bangalore Prof. B.V.Sreekantan Member INSA Srinivasa Ramanujan Professor Tata Institute of Fundamental Research, Bombay Prof.S.K.Trehan Member Professor of Applied Mathematics Punjab University, Chandigarh Prof.J. C.B hattacharyya Member Director Indian Institute of Astrophysics, Bangalore Mr.M.Ramani Secretary to Council Administrative Officer Indian Institute of Astrophysics, Bangalore _.< :::J a. 53" :::J :::J (f).- ;::+ c CD -o ~.... o "'C:::r '< (f) 0" (J) 2.3 m VBT .with the new Boller and Chivens Spectrograph, equipped with an Astromed CCD at the Cassegrain focus The Year in Review The present period in review, being the final device developed in our laboratories, viz. a year of the Seventh Plan, saw some hectic ac­ digital automatic star changing device for the tivities on the instrumentation front in order to same telescope. The entire instrumentation for complete some of the projected facilities withm the Antarctic Solar Observations was also com­ targeted dates. The major activity was the instal­ pleted by the Instrumentation Cell. A group lation of the Cassegrain system on the Vainu from the National Physical Laboratory, New Bappu Telescope, which was promptly equipped Delhi, was so impressed by the operation of the with a modified Boller and Chivens spectro­ system during trials, that it requested our help in graph, obtained earlier from the Anglo Austra­ modifying their solar ultraviolet experiment, lian Observatory. Along with this, the installa­ proposed to be conducted from Antarctica. A he­ tion of another major facility of a remotely liostat system was promptly designed and deliv­ operated prime focus cage was also achieved; it ered before the team left m November 1989. A is now possible to operate the prime focus CCD different group from the same laboratory has camera from the telescope console, and guide now come up with a request for the fabrication the telescope through the use of an intensifier­ of yet another system with special features. CCD guider system. More facilities for remote Research into various aspects of astronomy control and operation of the VBT are on the and astrophysics was continued with ever in­ anvil, and expected to be installed before the creasing enthusiasm and zeal. In solar physics, next annual report is written. We are not very far the perennial interest in understanding the from our dream of operating telescopes at Kav­ granulation network resulted in several new alur from a console in Bangalore. ideas and information; these included a series of The task of introduction of the VBT National continuous observations, stretching over a few Facility to the scientific community in the coun­ days, from Antartica of the supergranular struc­ try was pursued with great enthUSiasm. The ture - the first observation of its kind by any VBT News Letters were circulated to more than Indian team. 150 centres; two workshops gathering current and potential users of the facility were arranged. Activities of our solar system research group A special winter school was held under the were rewarded when one of its discoveries was auspices of the Institute, drawing post graduate proved to be a hitherto unknown asteroid; the students and degree college teachers from all new minor planet has been named "Ramanujan" over the country, to enable them to learn and after the mathematical genius who had outshone understand the functioning and possibilities of many of his contemporaries and predecessors frontline observational astronomy in India. during his brief stay in the world. Incidentally, this is the first minor planet discovered by an The other national facility run by the Insti­ Indian scientist; only a handful of other in­ tute for prOVIding sophisticated instrumentation stances of similar discoveries from our country to astronomers was also kept busy by an in­ was by a British astronomer in the nineteenth creased volume of requests from scientific century. groups. The Uttar Pradesh State Observatory, Nainital requested a new driving system for the The availability of highly sensltlve CCD Sampurnanand Telescope, which has since been detectors at the focal planes of our major tele­ delivered; they have now requested another scopes has opened up the flood-gates of new 2 Indian Institute of Astrophysics observational data. Objects which had earlier universe, our scientists have found connections reqUIred a whole night's exposure can now be between the energy dependent super string ten­ captured in a few minutes. Utilizing these capa­ sion and fundamental physical constants. A bilities, new investigations on several types of study of the theory of strong gravity in five-di­ objects made spectacular progress. Symbiotic mensional Kaluza-Klein space-time was carried stars, B-emission stars, planetary nebulae and out in search of a physical significance of the long period Cepheids are some of the objects cosmological constant; the questions concerning which came under the intense gaze of our scien­ inflation and the formation of hierarchical struc­ tists. In some Be stars clear indications of mass tures were sought to be answered as a conse­ loss through stellar winds, outbursts and phase quence of Weyl gravity in the early universe. transitions were obtained. Generation, modification and propagation of radiation in the interiors of stars and superdense Supplementing all these, specially requested compact bodies were other heavily investigated observations through satellites IUE and IRAS, topics. revealed some of the enigmatic phenomena around astronomical objects. In a series of col­ I shall desist from listing other highly inter­ laborative efforts, our scientists pooled their data esting investigations in many fields of observa­ with others in a bid to unlock some of nature's tional and theoretical astrophysics and observ­ mysteries. able manifestations in our immediate neighbour­ hood. More details are given in the body of the Some of our collaborative efforts went even report; still more may be found in the extensive further. While many of our young scientists literature cited in the list of publications. spent nights at telescopes abroad, several foreign scientists came to spend their time with us, As in the previous year, this year too we had sharing their knowledge through discussions and the privilege of hosting the CSIR distinguished supplementing their information with the help of scientist's lecture in Bangalore; the speaker was our telescopes. This year we had collaborating Prof. S.Chandrasekhar, the doyen of the world scientists