National Academy of Sciences of the Republic of Armenia V.A. Ambartsumian Byurakan Astrophysical Observatory Proceedings of the Conference “Evolution of Cosmic Objects through their Physical Activity” dedicated to Viktor Ambartsumian’s 100th anniversary 15-18 September 2008 Yerevan - Byurakan, Armenia Editors: Haik Harutyunian, Areg Mickaelian, Yervant Terzian Yerevan “GITUTYUN” Publishing House of NAS RA 2010 1 г۳ëï³ÝÇ Ð³Ýñ³å»ïáõÃÛ³Ý ¶ÇïáõÃÛáõÝÝ»ñÇ ³½·³ÛÇÝ ³Ï³¹»Ùdz ì.Ð. гٵ³ñÓáõÙÛ³ÝÇ ³Ýí. ´Ûáõñ³Ï³ÝÇ ³ëïÕ³¹Çï³ñ³Ý ìÇÏïáñ гٵ³ñÓáõÙÛ³ÝÇ 100-³ÙÛ³ÏÇÝ ÝíÇñí³Í §îÇ»½»ñ³Ï³Ý Ù³ñÙÇÝÝ»ñÇ ¿íáÉÛáõóÇ³Ý Ýñ³Ýó ýǽÇÏ³Ï³Ý ³ÏïÇíáõÃÛ³Ý ÙÇçáóáí¦ ËáñÑñ¹³ÏóáõÃÛ³Ý ÝÛáõûñÇ ÅáÕáí³Íáõ 2008Ã. ë»åï»Ùµ»ñÇ 15-18 ºñ¨³Ý - ´Ûáõñ³Ï³Ý, г۳ëï³Ý ÊÙµ³·ÇñÝ»ñ: гÛÏ Ð³ñáõÃÛáõÝÛ³Ý, ²ñ»· ØÇù³Û»ÉÛ³Ý, ºñí³Ý¹ »ñ½Û³Ý ºñ¨³Ý ÐÐ ¶²² §¶ÆîàôÂÚàôܦ Ññ³ï³ñ³ÏãáõÃÛáõÝ 2010 2 IDS 06 Proceedings of the Conference “Evolution of Cosmic Objects through their Physical Activity”, dedicated to Viktor Ambartsumian’s 100th anniversary, held on 15-18 September 2008 in Yerevan-Byurakan, Armenia. Editors: Haik Harutyunian, Areg Mickaelian, Yervant Terzian. Yerevan: “Gitutyun” Publishing House of NAS RA, 2010, 355 pages, including figures. The book presents papers of the Proceedings of the conference dedicated to Viktor Ambarstumian’s 100 anniversary held in 2008 in Yerevan and Byurakan. It is divided into 5 parts related to the sessions held during the conference: Stars and Nebulae, Pulsars / Neutron Stars, Activity in Galaxies, Cosmology, Light Scattering and Radiative Transfer, and Miscellanea. All these fields reflect extremely productive results and achievements obtained by Viktor Ambarstumian during his long scientific life. Most of the authors have used Ambarstumian’s ideas to obtain new results and give new interpretations on various cosmic phenomena, which come to prove the importance of Ambarstumian’s works nowadays too. The book also includes a preface by the editors, the list of participants of the conference, report on the opening session at NAS RA, and author index at the end. ISBN 978-5-8080-0834-2 © V.A. Ambartsumian Byurakan Astrophysical Observatory, 2010 3 Viktor Ambartsumian (1908-1996) 4 PREFACE Victor Ambartsumian’s scientific heritage is rather voluminous and diversified. His first scientific papers were devoted to some actual problems of mathematical and theoretical physics, the quantum field theory and the structure of atomic nuclei, the age of the Universe and radiation transfer theory, and other topics. These studies of the 30s and 40s of the last century had a theoretical nature, were highly mathematical, and pioneered new mathematical methods of analyses. Later on the elegant mathematical computations were substituted for studies of more physical problems. Of course, such a differentiation of the sphere of his scientific interests is rather arbitrary and all his scientific researches originated from physical problems but with mathematical rigor. Twenty years ago S. Chandrasekhar noted: “Academician Ambartsumian’s realm does not divide astronomy and astrophysics into its conventional parts: theoretical and observational. He is an astronomer par excellence”. On the other hand, any historian of science could conclude that Ambartsumian had a special attitude towards unstable phenomena and he studied active processes taking place in various hierarchical levels of our universe during all his life. The phenomena of activity and instability of cosmic objects or their systems which are related to their structural, physical or other changes always hints at an evolutionary path to be found. Some of Ambartsumian’s results based on the study of activity (instability) processes are widely known. One can recall his ideas on the beta-decay or studies concerning the instability of planetary nebulae or “evaporation” of star clusters etc. However, the astronomical community worldwide is much more aware about his studies of stellar associations and active galactic nuclei. The first series of investigations led him to show in the 40s of last century the existence of young stars and consequently the continuing nature of the star formation process. Undoubtedly that was a very important astronomical result but also it had much deeper philosophical significance than solving a particular astronomical problem. Later the concept of the activity of galactic nuclei, put forward in the mid 50s received a hostile reception from the astronomical community without any exception. He was alone in his fight to promote the idea of the AGNs. Of course, both physical intuition and scientific competence were needed for arriving at an extraordinary for that time conclusion on the activity of galactic nuclei. However, these purely scientific qualities might have been insufficient if he had not personal courage helping him forward in an openly distrustful 5 atmosphere. Nowadays, after 50-60 years have elapsed, Ambartsumian’s ideas both in the field of star formation studies and AGN investigations are among the most actively developing scientific topics. Yet, new generations of astronomers working in these fields do not even know Ambartsumian’s name! The organizers of this meeting decided to dedicate this event to the active processes and their evolutionary significance indicating thus again the very important role Ambartsumian played in this area of research in revealing the evolutionary paths for cosmic objects. It is worth recalling his words on the activity phenomena in the galaxies: “These processes often reach such a large scale that they influence the appearance and integral parameters of the galaxies. Therefore the study of the nuclei and the study of the structure of galaxies with their evolutionary changes cannot be separated”. Nevertheless, the organizers of this meeting decided not to be very restrictive on the subject area of this conference. The meeting devoted to the centenary of a 6 great scientist cannot be limited in the frame of a very special subject only. That is why, many other reports not related to the activity phenomena have been accepted for the conference and are included in this volume as well. 87 scientists from 12 countries participated in the conference "Evolution of cosmic objects through their physical activity". Many of them personally knew Ambartsumian and some have worked with him as well. The volume is divided into 6 Sections according to the sessions held during the conference: Stars and Nebulae, Pulsars / Neutron Stars, Activity in Galaxies, Cosmology, Light Scattering and Radiative Transfer, and Miscellanea. Opening of V.A. Ambartsumian’s bust in front of the main builing of the Byurakan Observatory. Haik Harutyunian, Gennadi Mesyats, Radik Martirosyan, V.A. Ambartsumian’s sons Rafael and Ruben Ambartsumians. However, the Centennial meetings and celebrations took place during the whole year in 2008 at the Byurakan Astrophysical Observatory in Byurakan, Armenia, and also in Yerevan at the Armenian National Academy of Sciences. Most of the important events were organized in September around Ambarstumian’s birthday; there was a solemn meeting at the Armenian National Academy of Sciences on Sep 12, the international conference "Evolution of cosmic objects through their physical activity" on Sep 15-18, another conference “Physics of compact objects” on Sep 17-23 in Yerevan, opening of Ambartsumian’s bust in the Byurakan Observatory and visit to his cemetery on Sep 18, a ceremonial meeting and concert at the Opera House in Yerevan on Sep 19 (with 7 participation of the President of Armenia, Prime-Minister, Catolicos, and many important guests), and the Second Byurakan International Summer School for young astronomers “Practical Astrophysics” on Sep 20-30. In addition, a book with memories about V.A. Ambartsumian (compiled by E.S. Parsamian) was presented and distributed to the guests during the registration of the participants of the meeting. A DVD with all available information about Ambartsumian (compiled by A.M. Mickaelian, edited by H.A. Harutyunian) was released and presented on Sep 15 as well. In addition, H.A. Harutyuniana and A.M. Mickaelian prepared a booklet about Ambartsumian’s main scientific results and achievements; top 20 results entered this booklet together with some biographical data and other information and photographs. Ceremonial meeting and concert at the Yerevan Opera House on September 19, 2008. We would like to acknowledge support for organization of this conference by the Armenian Government, Armenain National Academy of Sciences (NAS RA), Byurakan Astrophysical Observatory (BAO), and the International Science and Technology Centre (ISTC). Haik Harutyunian, Areg Mickaelian, Yervant Terzian Editors Byurakan, Armenia and Ithaca, New York, USA August 2010 8 SCIENTIFIC ORGANIZING COMMITTEE (SOC) Halton Arp (Germany) Yuri Balega (Russia) Geoffrey Burbidge (USA), Co-chair Anatoly Cherepashchuk (Russia) Michael Dopita (Australia) Daniel Kunth (France) Hayk Harutyunyan (Armenia), Co-chair Jayant Narlikar (India) Sadanori Okamura (Japan) Elma Parsamian (Armenia) Roberto Terlevich (Mexico) Ian Robson (UK) David Sedrakian (Armenia) Yervant Terzian (USA) LOCAL ORGANIZING COMMITTEE (LOC) H.A.Harutyunian and A.M.Mickaelian, Co-Chairs, E.H. Nikoghosyan, Secretary, S.K.Balayan, A.L. Gyulbudaghyan, A.A.Hakobyan, T.Yu.Magakian, N.D. Melikyan, T.H.Movsessian, A.G.Nikoghossian, A.R.Petrosian 9 CONTENTS List of participants 13 Opening Session 15 Session 1. STARS AND NEBULAE B. Reipurth, C. Aspin – FUors and Early Stellar Evolution 19 T.Yu. Magakian, T.H. Movsessian, E.H. Nikogossian, T. Khanzadyan, E.R. 39 Hovhannesian, D.M. Sargsyan – Multi-Sided Studies of the Manifestations of Young Stellar Activity in Star Forming Regions G. Alecian – Will COROT satellite tell us whether HgMn stars pulsate or not? 55 Y. Terzian – Gaseous Nebulae: Astrophysical Laboratories in the Sky 56 A.L. Gyulbudaghian – OB-Assocoations and Molecular Clouds 62 A.G. Yeghikyan – On cosmic ray processing of ices in molecular clouds 70 R. Natsvlishvili, N. Kochiashvili – On a Mechanism of Stars’ Flares 77 N. Shakht – Observations of double and multiple stars by means of Pulkovo 26- 83 inch refractor A.