Download or read book X ray Spectral Properties of gamma ray Bursts written by and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors summarize the spectral characteristics of a sample of 22 bright gamma-ray bursts detected with the gamma-ray burst sensors aboard the satellite Ginga. This instrument employed a proportional and scintillation counter to provide sensitivity to photons in the 2--400 keV range, providing a unique opportunity to characterize the largely unexplored X-ray properties of gamma-ray bursts. The photon spectra of the Ginga bursts are well described by a low energy slope, a bend energy, and a high energy slope. In the energy range where they can be compared, this result is consistent with burst spectral analyses obtained from the BATSE experiment aboard the Compton Observatory. However, below 20 keV they find evidence for a positive spectral number index in approximately 40% of their burst sample, with some evidence for a strong rolloff at lower energies in a few events. They find that the distribution of spectral bend energies extends below 10 keV. The observed ratio of energy emitted in the X-rays relative to the gamma-rays can be much larger than a few percent and, in fact, is sometimes larger than unity. The average for their sample is 24%.
Download or read book Spectral Properties of Gamma ray Bursts Observed by the Burst and Transient Source Experiment written by Lyle A. Ford and published by . This book was released on 1996 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of the Temporal and Spectral Characteristics of Gamma Ray Bursts written by Jay Preston Norris and published by . This book was released on 1983 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gamma ray Bursts written by Juri Poutanen and published by . This book was released on 1999 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Papers from a February 1999 workshop discuss unresolved issues regarding prompt emission of gamma-ray bursts (GRBs). Themes are temporal properties, spectral properties, central engine and radiative mechanisms, spatial distribution, luminosity function, cosmological effects, and future missions. Specific topics include radiation from relativistic strongly magnetized outflows, quasi-thermal comptonization and GRBs, and cosmological signatures in temporal and spectral characteristics of GRBs. The volume lacks a subject index. The editors are affiliated with the Stockholm Observatory. Annotation c. Book News, Inc., Portland, OR (booknews.com)
Download or read book Gamma ray Bursts written by Cheng Ho and published by Cambridge University Press. This book was released on 1992-03-12 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarizes the current understanding of Astronomical gamma-ray bursts, short-lived flashes of high-energy radiation, which have eluded even a basic explanation for over twenty years, and describes directions for future research.
Download or read book On the Spectral Properties and High Energy Emission from Gamma Ray Bursts written by Paz Beniamini and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gamma ray Bursts and Compact X ray Binaries written by Neil Gehrels and published by . This book was released on 2007 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gamma Ray Bursts written by Gilbert Vedrenne and published by Springer Science & Business Media. This book was released on 2009-03-20 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since their discovery was first announced in 1973, gamma-ray bursts (GRBs) have been among the most fascination objects in the universe. While the initial mystery has gone, the fascination continues, sustained by the close connection linking GRBs with some of the most fundamental topics in modern astrophysics and cosmology. Both authors have been active in GRB observations for over two decades and have produced an outstanding account on both the history and the perspectives of GRB research.
Download or read book Spectral Properties of Gamma Ray Bursts Detected by the INTEGRAL Satellite written by Sinéad McGlynn and published by . This book was released on 2008 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Search for Discrete X Ray Spectral Features in a Sample of Bright Gamma Ray Burst Afterglows written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present uniform, detailed spectral analyses of gamma-ray burst (GRB) X-ray afterglows observed with ASCA, Beppo-SAX, Chandra, and XMM-Newton, and critically evaluate the statistical significances of X-ray emission and absorption features in these spectra. The sample consists of 21 X-ray afterglow observations up to and including that of GRB040106 with spectra of sufficient statistical quality to allow meaningful line searches, chosen here somewhat arbitrarily to be detections with more than 100 total (source plus background) counts. This sample includes all nine X-ray afterglows with published claims of line detections. Moderate resolution spectra are available for 16 of the 21 sources, and for the remaining five the Chandra transmission grating spectrometers obtained high-resolution data. All of the data are available from the public archive. We test a simple hypothesis in which the observed spectra are produced by a power-law continuum model modified by photoelectric absorption by neutral material both in our Galaxy and possibly also local to the burst. As a sample, these afterglow spectra are consistent with this relatively simple model. However, since the [chi][sup 2] statistic is not sensitive to weak and/or localized fluctuations, we have performed Monte Carlo simulations to search for discrete features and to estimate their significances. Our analysis shows that there are four afterglows (GRB011211, GRB030227, GRB021004, and GRB040106) with line-like features that are significant at the 3 [sigma] level. We cautiously note that, in two cases, the features are associated with an unusual background feature; in the other two, the fractional magnitudes of the lines are small, and comparable to the expected level of systematic uncertainty in the spectral response. In addition, none of the statistically significant features are seen in more than one detector or spectral order where available. We conclude that, to date, no credible X-ray line feature has been detected in a GRB afterglow. Finally, in a majority of cases, we find no evidence for significant absorbing columns local to the GRB host galaxy, implying there is little evidence from X-ray observations that GRB preferentially explode in high-density environments.
Download or read book A Study of the Temporal and Spectral Characteristics of Gamma Ray Bursts written by Jay Preston Norris and published by . This book was released on 1983 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding and Using Gamma Rays written by Alison Eldridge and published by Enslow Publishing, LLC. This book was released on 2021-12-15 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although only a small portion of the electromagnetic spectrum can be seen by the human eye, people depend on the energy from the waves in the electromagnetic spectrum every day. Gamma rays might be familiar from comic books and superhero movies, but few know that gamma ray bursts are the most spectacular explosions observed in the universe. This book gives readers a look into the discovery, history, and uses of gamma rays. It's a perfect complement to the Next Generation Science Standards in electromagnetic radiation, and a perfect glimpse into how electromagnetic radiation is affecting us every day.
Download or read book Gamma Ray Bursts in the Afterglow Era written by Enrico Costa and published by Springer Science & Business Media. This book was released on 2001-12-14 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: The information received from BeppoSAX, Chandra and other instruments in the last two years has more than doubled the number of samples of Gamma-Ray Bursts localized and followed up for afterglow search. This has also increased the interest of astronomers in GRBs. This book reviews the research of the last two years and covers the global properties of GRBs, GRB afterglows, GRB host galaxies, cosmology using GRBs, and theories for GRBs and their afterglows. Theoretical and observational aspects are presented as well as tools for the analysis of the data.
Download or read book Toward an Understanding of the Progenitors of Gamma Ray Bursts written by Joshua S. Bloom and published by Universal-Publishers. This book was released on 2002 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: The various possibilities for the origin ("progenitors") of gamma-ray bursts (GRBs) manifest in differing observable properties. Through deep spectroscopic and high-resolution imaging observations of some GRB hosts, I demonstrate that well-localized long-duration GRBs are connected with otherwise normal star-forming galaxies at moderate redshifts of order unity. Using high-mass binary stellar population synthesis models, I quantify the expected spatial extent around galaxies of coalescing neutron stars, one of the leading contenders for GRB progenitors. I then test this scenario by examining the offset distribution of GRBs about their apparent hosts making extensive use of ground-based optical data from Keck and Palomar and space-based imaging from the Hubble Space Telescope. The offset distribution appears to be inconsistent with the coalescing neutron star binary hypothesis (and, similarly, black-hole--neutron star coalescences); instead, the distribution is statistically consistent with a population of progenitors that closely traces the ultra-violet light of galaxies. This is naturally explained by bursts which originate from the collapse of massive stars ``collapsars''). This claim is further supported by the unambiguous detections of intermediate-time (approximately three weeks after the bursts) emission ``bumps'' which appear substantially more red than the afterglows themselves. I claim that these bumps could originate from supernovae that occur at approximately the same time as the associated GRB; if true, GRB 980326 and GRB 011121 provide strong observational evidence connecting cosmological GRBs to high-redshift supernovae and implicate massive stars as the progenitors of at least some long-duration GRBs.
Download or read book X Ray Timing and Cosmic Gamma Ray Bursts written by COSPAR. Scientific Commission E. E1.1 and E1.2 Symposia and published by Elsevier. This book was released on 1998-12-07 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Energy Emission from Pulsars and their Systems written by Nanda Rea and published by Springer Science & Business Media. This book was released on 2011-02-04 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of the inaugural meeting of the Sant Cugat Forum on Astrophysics was to address, in a global context, the current understanding of and challenges in high-energy emissions from isolated and non-isolated neutron stars, and to confront the theoretical picture with observations of both the Fermi satellite and the currently operating ground-based Cherenkov telescopes. Participants have also discussed the prospects for possible observations with planned instruments across the multi-wavelength spectrum (e.g. SKA, LOFAR, E-VLT, IXO, CTA) and how they will impact our theoretical understanding of these systems. In keeping with the goals of the Forum, this book not only represents the proceedings of the meeting, but also a reflection on the state-of-the-art in the topic.
Download or read book Gamma Ray Bursts 30 Years of Discovery written by E.E. Fenimore and published by American Institute of Physics. This book was released on 2004-10-21 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last thirty years, gamma-ray bursts have grown from an oddity to a central position in astrophysics. Not only are they the largest explosions since the big bang, capable of flooding most of the universe with gamma-rays, but their brilliance serves as a backlight that can illuminate the cosmos far deeper into the early universe than any other object. Their unpredictability has forced researchers to use extreme measures to observe them: completely autonomous satellites and robotic ground-based telescopes. Their bizarre physical properties have pushed us to develop new theories of astrophysical explosions. Topics include: global properties of GRBs; X-ray flashes; ultra-high energy gamma-rays, neutrinos, gravity waves; prompt emission and early afterglows; relativistic jets and polarization; GRB030329; GRB progenitors; GRB connection to supernovae; dark versus bright GRBs; late afterglows; GRBs and cosmology; general observations; general theory; analysis and observation techniques; present satellites; Swift satellite; future satellites; and robotic observing systems.
