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This volume includes the papers presented during the high energy session of the first Orbis Scientiae held by the Center for Theo­ retical Studies, University of Miami. The Orbis met from January 7th to 12th, 1974 for the purpose of allowing scientists in various dis­ ciplines to acquaint each other with frontier problems of their respective disciplines. This Orbis Scientiae was the first of a new series of annual gatherings which have replaced the Coral Gables Conferences. These new meetings will include, in addition to physics, the main­ stay of the Coral Gables Conferences, other sciences and will allow scientists in the various disciplines represented to exchange views with each other as well as among them­ selves. The high energy sessions of the Orbis were devoted primarily to fundamental theories which attempt to unify a number of interactions in physics such as the electromagnetic and gravi­ tational forces, the electromagnetic and weak forces, or indeed all of the known interactions. Papers were also invited on other topics of cur­ rent interest in high energy physics and astro­ physics and they form part of this volume. v PREFACE This volume is not subdivided but the first half is devoted to fundamental theories and the second half to other subjects of current interest. The last paper, on stellar evolution, was presented at the Sixth Annual J. Robert Oppenheimer Memorial Prize Ceremonies by the recipient, Professor Edwin E. Salpeter of Cornell University.

The IAU Colloquium No. 59,'The effects of mass loss on Stellar Evolution'was held on September 15-19, 1980 at the International Centre for Theoretical Physics, Miramare, Trieste (Italy), under the auspices of the IAU Executive Co~ mittee and the Italian National Council of Research. The planning of this conference began two years ago du­ ring the IAU Symposium No. 83'Mass loss and evolution of 0 type stars'(Qualicum Beach, Victoria, Canada) when we felt that mass loss and its effects on the evolution of stars was too broad a subject for being confined to 0 type stars only. Therefore we thought that a conference dealing with the general problem of mass loss across the whole HR diagram would have been of interest to all people working in the field. The main idea was that bringing together Astronomers and Astrophysicists of the widest range of interests and e~ pertize - all in some way related to the problem of mass loss from stars - would have spurred thorough discussions on the many aspects and implications of this topic. We hope this goal has been achieved. Furthermore, the most recent observational and theoreti­ cal developments on the problem of mass loss from early ty­ pe stars avoided this meeting to be a simple updating of the Qualicum Beach Symposium as far as this issue is concerned.

Proceedings of the 69th Colloquium of the International Astronomical Union held in Bamberg, F.R.G., August 31-September 3, 1981

Proceedings of a Symposium held in Dwingeloo, The Netherlands, September 24-26, 1984 in honour of Adriaan Blaauw on the occasion of his 70th birthday

lAD Symposium No. 66 was held in Warsaw from September 10th to September 12th 1973, in connection with the Extraordinary General Assembly of the lAD. It was arranged by lAD Symposium No. 35 and the Scientific Organising Committee con­ sisted of A. G. Massevitch (Chairman), A. V. Tutukov (Secretary), H. M. van Horn, N. Dallaporta, J. P. Ostriker, B. Paczynski, G. Ruben, E. Schatzman, R. J. Tayler and A. Weigert. This volume contains the full texts of all of the invited papers presented at the Symposium, apart from that delivered by R. P. Kraft, which is published in abstract because it is appearing in full elsewhere. In addition the short communications given at the Symposium are published in abstract. I attempted to take down all of the dis­ cussion as it occurred and all contributors to the discussion were asked to provide copies of their remarks. From these sources an edited version of the discussion has been produced. As the final version has not been seen by the contributors, I should be held responsible for all errors. At Warsaw, some of the short communications did not immediately follow the invited paper to which they referred. In the printed version they and any discussion relating to them are placed in the most logical position. A small number of short communications, which were circulated in abstract at Warsaw but which were not delivered orally, are also included in the published version.

Fundamental unsolved problems of stellar astrophysics include the effects of angular momentum on stellar structure and evolution, the nature and efficiency of the processes by which angular momentum is redistributed within and lost from stars, and the role that stellar rotation plays in enhancing or driving stellar mass loss. There appears to be a qualitative change in the nature and efficiency of these mechanisms near spectral type FO: hotter (more massive) stars typically retain more angular momentum at least until they reach the main sequence, while cooler stars typically spin down quickly. For the hotter stars, recent work suggests a strong link between the type of pulsation behavior, the mass loss rates, and the rotation velocity. If the same mechanisms are able to drive mass loss from the main sequence A stars, as has recently been proposed, then the current interpretations of a number of observations will be drastically affected: e. g. the ages of clusters may be incorrect by up to a factor of two, and the surface abundances of isotopes of He, Li and Be may no longer give constraints on cosmological nucleosynthesis. There are also effects on the evolution of the abundances of elements in the interstellar medium and on the general evolution of populations of stars. Thus the questions of the mechanisms of angular momentum and mass loss of stars more massive than the sun is important not only for stellar studies but for the foundations of much of modern astrophysics.

The origin of stars is one of the principle mysteries of nature. During the last two decades advances in technology have enabled more progress to be made in the quest to understand stellar origins than at any other time in history. The study of star formation has developed into one of the most important branches of mod­ ern astrophysical research. A large body of observational data and a considerable literat ure now exist concerning this topic and a 1arge community of international astronomers and physicists devote their efforts attempting to decipher the secrets of stellar birth. Yet, the young astronomerjphysicist or more advanced researcher desiring to obtain a basic background in this area of research must sift through a very diverse and sometimes bewildering literature. A literature which includes research in many discip1ines and sub discip1ines of classical astrophysics from stel­ lar structure to the interstellar medium and encompasses the entire range of the electromagnetic spectrum from radio to gamma rays. Often, the reward of a suc­ cessfu1 foray through the current literature is the realization that the results can be obsolete and outdated as soon as the ink is dry in the journal or the conference proceeding in which they are published.

Over the last decade we have witnessed a rapid change in our understanding of the late stages of stellar evolution. A major stimulus to this has been the synthesis of observational data from different wavebands of the electromagnetic spectrum. The advent of infrared astronomy has led to the discovery of many luminous. late-type stars obscured by their circumstellar dust envelope. Sources discovered in the IRC and AFGL infrared sky surveys were followed up by radio observa­ tions, leading to the widespread use of the OH and CO molecules as probes of the circumstellar envelopes. Advances in the technique of aperture synthesis have made possible observations with unprecedent resolving power, both in spectral-line and continuum. The success of the recent IRAS sky survey, with the detection of over 250,000 sources, brings the promise of even more exciting years ahead. This area of astronomical research is also blessed with the close collaboration between theorists and observers. New ideas are constantly being quantitatively tested by new data. Theoretical predictions are eagerly used as guides for further observations. This conference was initiated with the following objective: bring together workers in optical, infrared, radio and theoretical astronomy and let them confront each other. Based on the post-conference res­ ponses we received, many of the participants have indeed found this Workshop a stimulating experience. The Workshop on the Late Stages of Stellar Evolution was held from 2-5 June 1986 in Calgary, Canada.

This book reports the Proceedings of the NATO Advanced Research Workshop on'An­ gular Momentum Evolution of Young Stars'held from 17 to 21 September 1990 at Noto, Italy. The workshop had its immediate origin in a discussion about the availability of stel­ lar rotation data, that took place in 1987 at Viana do Castelo Portugal during the NATO meeting, Formation and Evolution of Low Mass Stars. We recognized that nearly 20 years had passed since the last meeting on stellar rotation and that significant progress in the observation of rotation rates in low mass stars had been made. During the last 20 years, new efficient instrumentation (CCD and photon counting de­ tectors and echelle spectrographs) and new analysis techniques (profile Fourier analysis) have allowed us to measure rotational velocities as low as 1-2 km/s and to reach low mass stars in young clusters. Even with these advances, rotational velocities of low mass stars would have remained challenging to determine if all single, low mass stars later than GO had rotational velocities of order or less than 10 km/sec. Evidence that this is not always the case was first provided by the photometric variability data obtained by van Leeuwen and Alphenaar for K dwarfs in the Pleiades and more recently by the vsini measurements of low mass stars in several young clusters.

The exploration of the first billion years of the history of the Universe, from the so-called Dark Ages to cosmic reionisation, represents one of the great challenges of contemporary astrophysics and one of the main drivers for future observational facilities. The book contains the elaborated notes of lectures given at the 36th Saas-Fee Advanced Course'First Light in the Universe'by three eminent scientists in the field: Abraham Loeb, Andrea Ferrara, and Richard Ellis. The formation of the first stars and black holes, the initial mass function, feedback effects, early dust formation, the history of cosmic star formation, distant galaxies, cosmic reionisation and the cosmic infrared background are the main topics treated. This book provides an accessible and up-to-date review of the field and will be useful to graduate students of astronomy, cosmologists, physicists and researchers.

Three eminent scientists, each well known for the clarity of their writing, present for students and researchers what is known about the internal structure, origin and evolution of White Dwarfs, Neutron Stars and Black Holes, all objects at the final stage of stellar evolution. They cover fascinating topics such as pulsation of white dwarfs, millisecond pulsars or the dynamics around black holes. The book is written for graduate students in astrophysics, but is also of interest to professional astronomers and physicists.

The European Workshop on Astronomical Molecules was held at ‘The Conference Building'in Zwolle, the Netherlands, on 18–20 February 2004. The idea behind the workshop was to bring together astronomers studying similar processes in different astrophysical environments; masers and dense molecular gas around young stars and galactic nuclei. There is considerable overlap in physical and chemical phenomena between these environments, with scales ranging from circumstellar to central regions of galaxies. The workshop became a meeting place of observers and theorists as well as young and senior astronomers. The venue of the meeting facilitated continuous stimulated discussions in a relaxed atmosphere throughout the meeting and after sessions in the hotspots of the cosy town of Zwolle. This issue includes 12 reviews and 27 contributed papers presented in this Wo- shop, all of them were refereed by invited speakers or the editors. The quality of the papers is outstanding. The projects discussed here are often in an early stage and undoubtedly their progress has bene?ted greatly from the opportunity to discuss results with the experts in a wide range of areas. Similarly, we feel con?dent that the interaction of specialists with different backgrounds will initiate many new projects and collaborations. The format of the meeting was special since all participants were given the opportunity to make an oral presentation and there were no posters. In addition, the schedule allowed suf?cient room enough for off-line presentations and discussions.

This is the proceedings of the International Symposium on Origin of Matter and Evolution of Galaxies which was held near Tokyo, Japan, in November 2003. The meeting brought together many scientists from vast fields — nuclear physics, particle physics, cosmic-ray physics, cosmology, astronomy, geophysics, and others — to promote discussion and collaboration.The proceedings have been selected for coverage in:• Index to Scientific & Technical Proceedings® (ISTP® / ISI Proceedings)• Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings)• CC Proceedings — Engineering & Physical Sciences

Theideatocelebrate50yearsoftheSalpeterIMFoccurredduringtherecent IAU General Assembly in Sydney, Australia. Indeed, it was from Australia that in July 1954 Ed Salpeter submitted his famous paper'The Luminosity Function and Stellar Evolution'with the rst derivation of the empirical stellar IMF. This contribution was to become one of the most famous astrophysics papers of the last 50 years. Here, Ed Salpeter introduced the terms'original mass function'and'original luminosity function', and estimated the pro- bility for the creation of stars of given mass at a particular time, now known as the'Salpeter Initial Mass Function', or IMF. The paper was written at the Australian National University in Canberra on leave of absence from Cornell University (USA) and was published in 1955 as 7 page note in the Astroph- ical Journal Vol. 121, page 161. To celabrate the 50th anniversary of the IMF, along with Ed Salpeter's 80th birthday, we have organized a special meeting that brought together scientists involved in the empirical determination of this fundamental quantity in a va- ety of astrophysical contexts and other scientists fascinated by the deep imp- cations of the IMF on star formation theories, on the physical conditions of the gas before and after star formation, and on galactic evolution and cosmology. The meeting took place in one of the most beautiful spots of the Tuscan countryside, far from the noise and haste of everyday life.

This book focuses on current topics in astronomy, astrophysics and nuclear astrophysics. The areas covered are: origin of the universe and nucleosynthesis; chemical and dynamical evolution of galaxies; nova/supernova and evolution of stars; astrophysical nuclear reaction; structure of nuclei with unstable nuclear beams; origin of the heavy element and age of the universe; neutron star and high density matter; observation of elements; high energy cosmic rays; neutrino astrophysics.

The 16th volume in the annual series on recent developments and scientific progress in astronomy and astrophysics contains thirteen invited reviews presented during the International Scientific Conference of the Society on'The Cosmic Circuit of Matter', held in Berlin, Germany. Readers also learn about the lecture on the behaviour of stars by infrared interferometry given by Charles H. Townes, Berkeley, USA who was awarded the Karl Schwarzschild medal 2002. Further contributions on the topic provide, among other, the latest results on the Solar atmosphere, formation of stars, substellar objects, galaxies and clusters of galaxies.

The papers in this volume present a recent survey of important results in the field of supernovae and pulsars. The review articles are likely to prove valuable because of their pedagogical nature to students and other entrants in the field. For researchers already working in this field, observational results and the details of theoretical investigations presented systematically are likely to stimulate further debates regarding classification of supernovae types Ia Ib and II and their progenitors and their relationship. New results are presented.

'This report is based in part on the presentations made at the Workshop on Substellar-Mass Objects (WSMO)... held in Irvine, California, on January 24-25, 1998'--p. vii.