Cosmic Gamma-Ray Sources, 2004
Astrophysics and Space Science Library Series, Vol. 304

Gamma-ray astronomy has undergone an enormous progress in the last 15 years. The success of satellite experiments like NASA's Comp­ ton Gamma-Ray Observatory and ESA's INTEGRAL mission, as well as of ground-based instruments have open new views into the high-energy Universe. Different classes of cosmic gamma-ray sources have been now detected at different energies, in addition to young radio pulsars and gamma-ray bursts, the classical ones. The new sources include radio­ quiet pulsars, microquasars, supernova remnants, starburst galaxies, ra­ dio galaxies, flat-spectrum radio quasars, and BL Lacertae objects. A large number of unidentified sources strongly suggests that this brief enumeration is far from complete. Gamma-ray bursts are now estab­ lished as extragalactic sources with tremendous energy output. There is accumulating evidence supporting the idea that massive stars and star forming regions can accelerate charged particles up to relativistic ener­ gies making them gamma-ray sources. Gamma-ray astronomy has also proved to be a powerful tool for cosmology imposing constraints to the background photon fields that can absorb the gamma-ray flux from dis­ tant sources. All this has profound implications for our current ideas about how particles are accelerated and transported in both the local and distant U niverse. The evolution of our knowledge on the gamma-ray sky has been so fast that is not easy for the non-specialist scientist and the graduate student to be aware of the full potential of this field or to grasp the fundamentals of a given topic in order to attempt some original contribution.

1 Introduction.- 1 The early years of gamma-ray astronomy.- 2 The age of the spark chambers.- 3 The Compton gamma-ray observatory.- 4 Gamma-ray line astronomy.- 5 The development of ground-based high-energy gamma-ray astronomy.- 6 Cosmic gamma-ray sources.- 7 Suggested reading.- 2 Fundamentals of gamma-ray astrophysics.- 1 Basic concepts.- 2 Gamma-ray production: thermal mechanisms.- 3 Non-thermal gamma-ray production: particle—field interactions.- 4 Non-thermal gamma-ray production: particle-matter interactions.- 5 Gamma-ray line production.- 6 Gamma-ray absorption processes.- 7 Doppler and gravitational shifts of gamma rays.- 8 Related physical processes.- 3 Galactic gamma-ray sources.- 1 Young sources in star-forming regions.- 2 Variable sources in the inner spiral arms.- 3 Variable sources in the halo.- 4 Extragalactic gamma-ray sources.- 1 Low-, mid-, and high-latitude sources.- 2 The case for AGNs.- 3 EGRET observations of AGNs.- 4 Microlensing of -?-ray blazars.- 5 Alternative origins of high-latitude ?-ray sources.- 6 EGRET detections and cosmic rays.- 7 Concluding remarks.- 8 Acknowledgments.- 5 Non-thermal emission from early-type binaries.- 1 Some basic considerations.- 2 Non-thermal radio emission from early-type stars.- 3 Inverse Compton scattering.- 4 Other ?-ray emission mechanisms.- 5 Conclusions and future perspectives.- 6 Gamma-ray emission from supernova remnants.- 1 Introduction.- 2 Structure and evolution of SNRs.- 3 Particle acceleration in supernova remnants.- 4 Gamma-ray emission from supernova remnants.- 5 Supernova remnants and unidentified gamma-ray sources.- 6 The future of high-energy studies of supernova remnants.- 7 Gamma ray pulsars.- 1 Gamma-ray pulsar multiwavelength light curves.- 2 Gamma-ray pulsar multiwavelength energyspectra.- 3 Other candidate isolated neutron stars.- 4 Gamma-ray pulsars compared to the general pulsar population.- 5 Pulsars at the highest energies.- 6 Future pulsar observations at high energies.- 7 Summary.- 8 Theories of gamma-ray emission from pulsars.- 1 Basic properties of pulsars.- 2 Gamma-ray observations associated with pulsars.- 3 Theories of gamma-ray emission from regions within the light cylinder.- 4 Gamma-ray emission from regions beyond the light cylinder.- 5 Mature gamma-ray pulsars and unidentified gamma-ray sources in the Galaxy and in the Gould Belt.- 6 Discussion.- 9 High energy emission from microquasars.- 1 Introduction: what is a microa uasar?.- 2 X-ray emission from jets?.- 3 High-energy ?-ray emission.- 4 Predictions.- 5 Synchrotron self-Comptonization models.- 6 External Comptonization models.- 7 Hadronic jet models.- 8 Gamma-ray lines.- 9 Why are there so few sources, and how do we find more?.- 10 Conclusions.- 10 Gamma-ray bursts.- 1 The standard fireball shock model.- 2 Post-standard effects.- 3 Further topics.- 11 Clusters of galaxies at high energy gamma-rays.- 1 Gamma-ray identification of individual galaxy clusters.- 2 Spatial-statistical correlation studies.- 3 Contribution of unresolved galaxy clusters to the EGDB.- 12 Diffuse gamma rays.- 1 Gamma rays and cosmic rays connection.- 2 Cosmic rays.- 3 Galactic structure.- 4 Diffuse galactic gamma-ray emission.- 5 Extragalactic diffuse emission.- 6 Faint sources.- 7 Tracers of exotic Physics ?.- 8 Broader picture and future perspective.- 13 Multifrequency strategies for the identification of gamma-ray sources.- 1 Introduction and historical overview.- 2 Blazars and EGRET unidentified sources.- 3 EGRET sources and radio galaxies.- 4 Radio quiet isolated neutron stars.- 5 Young pulsarcandidates.- 6 Other source classes.- 7 Studies of EGRET unidentified sources at TeV energies.- 14 Future ground-based TeV gamma-ray telescopes.- 1 Detection technique.- 2 Observational status.- 3 The next generation of imaging telescopes.- 4 Future prospects.- 5 Acknowledgements.- 15 GLAST: Understanding the high energy gamma-ray sky.- 1 Instrument description.- 2 Prospects: known and potential ?-ray sources.- 3 Conclusions.- Author Index.- Object Index.