Galactic Astrophysics and Gamma-Ray Astronomy


Book Description

This book contains the invited and contributed lectures presented at a meeting organised in the context of the XVIII general assembly ofthe IAU, held in Patras, August 19, 1982. Roughly one hundred scientists attended this meeting, the discussions were livel- sometimes heated - and the original time span allocated to the meeting was as a result, comfortably exceeded by about 50 % . The aim of this meeting was to determine the role of galactic gamma-ray astronomy within the general concept of galactic astrophysics. The timing, at the end of the COS-B mission, was regarded as opportune, because it gives interested astrophysicists the possibility for interdisciplinary studies using the existing gamma-ray data base (e.g. comparison with infrared, radio, X-ray, etc. astronomies), as well as for theoretical studies. The next generation of gamma-ray detectors will probably not be in operation for another 5 to 10 years, and therefore it is hoped that the proceeding of this meeting can be used (in the intermediate time) as a basis for further studies, as a stimulation for more theoretical work and as an important contribution for defining the aims and operation of future gamma-ray missions. The interrelationship with other branches of astronomy, the astrophysical implications and the study of relevant physical processes using available measurements in the near-Earth environment were important results of the meeting. Many persons contributed to the success of the meeting, in particular all those who either presented a contribution and/or took part in the discussions.




Gamma-ray Astronomy


Book Description

The recent launch of NASA's Gamma-Ray Observatory will increase interest in gamma-ray astronomy. This is a fully up-dated new edition of the authors' earlier volume published in 1986 and covers both the background science and the current state-of-the-art in this field. The emphasis is on the astronomy and astrophysics of known sources of cosmic gamma-rays outside the solar system. The authors discuss the mechanisms for the production and absorption of gamma-rays. The gamma-ray line astronomy of the interstellar medium, galactic centre, and various discrete sources is then considered. Gamma-ray bursts are treated in considerable detail in chapter three, and the final two chapters describe medium energy and ultra-high energy gamma-rays. Relevant data from supernova SN1987A is also included in this edition. The book includes comprehensive references to the primary literature, together with many figures and tables. The concentration on phenomenology makes this book a fine introduction to gamma-ray astronomy.




Gamma Ray Astrophysics


Book Description




The Universe in Gamma Rays


Book Description

After describing cosmic gamma-ray production and absorption, the instrumentation used in gamma-ray astronomy is explained. The main part of the book deals with astronomical results, including the somewhat surprising result that the gamma-ray sky is continuously changing.




Cosmic Gamma Rays, Neutrinos, and Related Astrophysics


Book Description

Proceedings of the NATO Advanced Study Institute, Erice, Sicily, Italy, April 20-30, 1988




Gamma-Ray Astronomy


Book Description

Gamma-ray astronomy gives us a view of the Universe through the most recent window to have been opened. The emphasis in this account is firmly on the astronomy and astrophysics of known sources of cosmic gamma-rays outside the solar system. The authors first introduce the mechanisms for the production and absorption of gamma-rays. The line astronomy of the interstellar medium, galactic centre, and various discrete sources is then discussed. Gamma-ray bursts are treated in considerable detail, in view of the need for a comprehensive review of this important topic. The two final chapters describe medium energy and ultra-high energy gamma rays. This book includes comprehensive references to the primary literature, together with tables and graphs.







Very High Energy Gamma-Ray Astronomy


Book Description

High energy gamma-ray photons are the prime probes of the relativistic or high-energy universe, populated by black holes, neutron stars, supernovae, quasars, and matter-antimatter annihilations. Through studying the gamma-ray sky, astrophysicists are able to better understand the formation and behavior of these exotic and energetic bodies. V




Gamma-Ray Astronomy


Book Description

Observation of discrete energy electromagnetic emissions from celestial objects in the radio, IR, optical, lN, and X-ray spectral regions has dramatically advanced our know ledge in the field of astrophysics. It is expected that identification of nuclear 'Y-ray line emissions from any cosmic source would also prove to be a powerful new tool for probing the Universe. Since the publication of Morrison's work in 1958, many experiments were carried out searching for evidence of 'Y-ray lines from cosmic sources, however with little success. Only a few positive experimental results have been reported, in spite of an expenditure of considerable effort by many people: in particular, the possible Galactic Center emission line (473 to 530keV) and 'Y-ray lines at several energies (e. g. , 0. 5 MeV and 2. 2 MeV) associated with large solar flares. Both of these observations are unconfirmed by indepen dent observations (ca. 1975). The high energy 'Y-rays (>30MeV) from the Galactic Center are at least partly due to the decay of 1[0 mesons, which are of unique energy (67. 5 MeV) in the 1[0 rest frame only. The reasons for the limited amount of data avail able in this field, even though early theoretical predictions were very optimistic regarding fluxes of nuclear lines, are that experimental efforts are plagued with high backgrounds and low fluxes, and that development of instruments with telescopic properties in the energy range of interest is difficult.




Very High Energy Cosmic Gamma Radiation


Book Description

Gamma ray astronomy, the branch of high energy astrophysics that studies the sky in energetic ?-ray photons, is destined to play a crucial role in the exploration of nonthermal phenomena in the Universe in their most extreme and violent forms. The great potential of this discipline offers impressive coverage of many OC hot topicsOCO of modern astrophysics and cosmology, such as the origin of galactic and extragalactic cosmic rays, particle acceleration and radiation processes under extreme astrophysical conditions, and the search for dark matter."