Download or read book The Study of the Seyfert Galaxy NGC 4151 with the Scintillation Imaging Gas filled Hard X ray Telescope SIGHT written by Ann Marie Parsons and published by . This book was released on 1993 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1994 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1993 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Further Spectroscopic Observations of the Nucleus of the Seyfert Galaxy NGC 4151 written by Kurt S. Anderson and published by . This book was released on 1971 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Gamma Ray Observatory written by and published by . This book was released on 1991 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Gamma Ray Observatory written by United States. National Aeronautics and Space Administration and published by . This book was released on 1990 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Seyfert Galaxy NGC 4151 written by Hartmut Schulz and published by . This book was released on 1995 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Detection of Soft Gamma Ray Emission from the Seyfert II Galaxy NGC 4507 by the OSSE Telescope Preprint written by and published by . This book was released on 1995 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the first soft gamma-ray observation by the OSSE experiment onboard the CGRO of the optically selected Seyfert II galaxy, NGC 4507. The source was observed on two separate weeks in 1993 and detected between 50 and 200 keV at a confidence level of 7 . There is no evidence of flux variability within or between the two observation periods which sample timescales from days to months. The source spectrum obtained from combining the two sets of data is best described by spectral forms including some exponential cutoff. The observed shape is steeper than the one observed by GINGA in the X-ray band in 1990. The joint GINGA/OSSE spectrum is best described by an absorbed power law exponentially cutoff at high energies and having an iron K alpha emission line. Comparison between NGC 4507 and other Seyfert galaxies indicate that although at low energies a difference between type I and II objects is possible (but still weak in this specific case) at high energies the observed shapes are indeed similar. We interpret this as evidence that the primary source emission (i.e. not reprocessed by material in the source) is the same for both types; this finding is in agreement with the unified scheme of Seyfert galaxies. Apart from its own interest, the OSSE detection of hard X-ray emission from a Seyfert II galaxy is also important for the implications it has on the contribution of Seyfert galaxies of both types to the cosmic diffuse background, as type II objects are expected to outnumber type I sources.
Download or read book Radio X ray Variability and Structure Investigation of Seyfert Galaxy NGC 4051 written by Sadie Jones and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physical Conditions in the X ray Emission line Gas in the Seyfert 2 Galaxy Ngc 1068 written by Neetika Sharma and published by . This book was released on 2016 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Active Galactic Nuclei (AGN) reside in the centers of many (10%) galaxies. The nuclear spectra exhibit a broad (from radio to gamma-rays) non-stellar continuum which exceeds the luminosity of the host. AGN are thought to be powered by accretion of matter onto a supermassive black hole (BH~10^6-10^9 times the mass of the Sun). Since this activity takes place in a relatively small region (“3 light years), the central engine of even the closest AGN cannot be imaged directly with current technology. Nevertheless, spectroscopic observations can help us constrain the conditions of the gas very close to the BH.
Download or read book The Gamma Ray Observatory written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-13 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: An overview is given of the Gamma Ray Observatory (GRO) mission. Detection of gamma rays and gamma ray sources, operations using the Space Shuttle, and instruments aboard the GRO, including the Burst and Transient Source Experiment (BATSE), the Oriented Scintillation Spectrometer Experiment (OSSE), the Imaging Compton Telescope (COMPTEL), and the Energetic Gamma Ray Experiment Telescope (EGRET) are among the topics surveyed. Unspecified Center ...
Download or read book An imaging gas scintillation spectrometer for X ray astronomy written by Dirk G. Simons and published by . This book was released on 1988 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fifty Years of Quasars written by Mauro D'Onofrio and published by Springer. This book was released on 2014-10-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 50th anniversary of the discovery of quasars in 1963 presents an interesting opportunity to ask questions about the current state of quasar research. Formatted as a series of interviews with noted researchers in the field, each of them asked to address a specific set of questions covering topics selected by the editors, this book deals with the historical development of quasar research and discusses how advances in instrumentation and computational capabilities have benefitted quasar astronomy and have changed our basic understanding of quasars. In the last part of the book the interviews address the current topic of the role of quasars in galaxy evolution. They summarise open issues in understanding active galactic nuclei and quasars and present an outlook regarding what future observational facilities both on the ground and in space might reveal. Its interview format, the fascinating topic of quasars and black holes, and the lively recollections and at times controversial views of the contributors make this book both rewarding and a pleasure to read!
Download or read book Gamma Ray Astrophysics written by Carl E. Fichtel and published by . This book was released on 1981 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The X ray Background written by Xavier Barcons and published by Cambridge University Press. This book was released on 1992-07-31 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of the current observational knowledge and understanding of the cosmic X-ray background.
Download or read book The Universe in Gamma Rays written by Volker Schönfelder and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
