Download or read book High Spectral Resolution Observations of the Galactic X ray Bulge written by Lindsay E. Rocks and published by . This book was released on 2008 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Suzaku Studies of White Dwarf Stars and the Galactic X ray Background Emission written by Takayuki Yuasa and published by Springer Science & Business Media. This book was released on 2013-01-16 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a study of the origin of an apparently extended X-ray emission associated with the Galactic ridge. The study was carried out with broadband spectra obtained from mapping observations in the Galactic bulge region conducted in 2005–2010 by the Suzaku space X-ray observatory. The spectra were analyzed with a newly constructed X-ray spectral model of an accreting white dwarf binary that is one of the proposed candidate stars for the origin of the Galactic ridge emission in the higher energy band. Fitting of the observed Galactic ridge spectra with the model showed that there is another spectral component that fills the gap between the observed X-ray flux and the component expected from the accreting white dwarf spectral model in the lower energy band. This additional soft spectral component was nicely explained by an X-ray spectral model of normal stars. The result, together with previously reported high-resolution imaging results, strongly supports the idea that the Galactic ridge X-ray emission is an assembly of dim, discrete X-ray point sources.
Download or read book X Ray Astronomy with the Einstein Satellite written by R. Giacconi and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 331 pages. Available in PDF, EPUB and Kindle. Book excerpt: The meeting of the High Energy Astrophysics Division of the American Astronomical Society, held in Cambridge, Massachusetts on January 28- 30, 1980, marks the coming of age of X-ray astronomy. In the 18 years since the discovery of the first extrasolar X-ray source, Sco X-l, the field has experienced an extremely rapid instrumentation development culminating with the launch on November 13, 1978 of the Einstein Observatory (HEAO-2) which first introduced the use of high resolution imaging telescopes to the study of galactic and extragalactic X-ray sources. The Einstein Observatory instruments can detect sources as faint as 10-7 Sco X-lor about 17 magnitudes fainter. The technological developments in the field have been paralleled by a host of new discoveries: in the early 1960's the detection of 9 "X-ray stars", objects 10 times more luminous in X-rays than the Sun and among the brightest stellar objects at all wavelengths; in the late 1960's and early 1970's the discovery of the nature of such systems which were identified as collapsed stars (neutron stars and black holes) in mass exchange binary systems, and the detection of the first few extragalactic sources.
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 Evolution of Galactic X Ray Binaries written by J. Truemper and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: The idea to hold a conference on the Evolution of Close-Binary X-ray sources grew in the summer of 1984. At that time we were hoping that some new results would be harvested in the months to come which would stimulate further work. We were particularly looking towards the Euro pean X-ray Observatory, EXOSAT, for new contributions. How lucky we were; quite unexpected developments took place. Just prior to the conference, quasi-periodic oscillations (now known as QPO) were discovered in three bright low-mass X-ray binaries: GX 5-1, Sco X-1, and Cyg X-2. They played an important role at the meeting. The possibility that QPOs imply a neutron star magnetic dipole field, and a neutron star rotation period in the millisecond range, received a lot of attention. This is not surprising, as it lends support to the idea, suggested earlier, that the 6-msec binary radio pulsar PSR 1953+29 evolved from a stage in which it was a bright low-mass X-ray binary. There was special interest in the possibility of white dwarf collapse into a neutron star. This is a. particularly attractive way to form the bright low-mass X-ray binaries, often referred to as galactic bulge sources. It would allow for the possibility of a very young neutron star in a very old binary system. The relatively high magnetic fields that one could infer from QPO could then be explained.
Download or read book High Resolution X ray Observations of the Galactic Center Region written by Hiroshi Murakami and published by . This book was released on 2003 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Formation of Galactic Bulges written by C. Marcella Carollo and published by Cambridge University Press. This book was released on 1999 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bulges lie at the center of spiral galaxies. Until recently, they were thought to host uniquely old stellar populations and thus provide a key for understanding galaxy formation. Recent observations from the ground and space have drastically changed our view on the nature of bulges and shown that they can also contain dust, gas, and star-forming regions. This timely volume presents review articles by a panel of international experts who gathered at a conference at the Space Telescope Science Institute, Baltimore, to address several fundamental questions: What is a bulge? When and how did bulges form? And, on what timescales? This volume provides a state-of-the-art picture of our new understanding of these fundamental building-blocks of galaxies, and a stimulating reference point for all those interested in galaxy formation.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book X ray Timing and Spectral Observations of Galactic Black Hole Candidate XTE J1550 564 During Outburst written by Kaice Theodore Reilly and published by . This book was released on 2002 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1981 Part 2 written by S. Böhme and published by Springer Science & Business Media. This book was released on 2013-04-18 with total page 803 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1982 Part 2 written by Siegfried Böhme and published by Springer Science & Business Media. This book was released on 2013-11-09 with total page 857 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts, which has appeared in semi-annual volumes since 1969, is devoted to the recording, summarizing and indexing of astronomical publications throughout the world. It is prepared under the auspices of the International Astronomical Union (according to a resolution adopted at the 14th General Assembly in 1970). Astronomy and Astrophysics Abstracts aims to present a comprehensive documenta tion of literature in all fields of astronomy and astrophysics. Every effort will be made to ensure that the average time interval between the date of receipt of the original literature and publication of the abstracts will not exceed eight months. This time interval is near to that achieved by monthly abstracting journals, compared to which our system of accumu lating abstracts for about six months offers the advantage of greater convenience for the user. Volume 32 contains literature published in 1982 and received before February 11, 1983; some older literature which was received late and which is not recorded in earlier volumes is also included. We acknowledge with thanks contributions to this volume by Dr. J. Bou~a, Prague, who surveyed journals and publications in Czech and supplied us with abstracts in English.
Download or read book Cosmological Aspects of X Ray Clusters of Galaxies written by W.C. Seitter and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NATO Advanced Study Institute "Cosmological Aspects of X-Ray Clus ters of Galaxies" took place in Vel en , Westphalia, Germany, from June 6 to June 18, 1993. It addressed the fruitful union of two topics, cosmology and X-ray clus ters, both of which carry substantial scientific weight at the beginning of the last decenium of the last century in the second millenium of our era. The so far largest X-ray "All-Sky Survey", observed by the ROSAT X-ray satel lite, and ROSAT's deep pointed observations, have considerably enlarged the base of X-ray astronomy, particularly concerning extragalactic sources. Cosmology has gained significant impetus from the large optical direct and spectroscopic surveys, based on high quality 2-dimensional receivers at large telescopes and powerful scan ning devices, harvesting the full information 1 content from the older technique of employing photographic plates. Radioastronomy and IR-astronomy with IRAS, as well as r-astronomy with GRO, continue and strengthen the role of extragalactic research. The rapidly growing computer power in data reduction and data storage facilities support the evolution towards large-number statistics. A most significant push was given to early cosmology by the needs of physics in trying to unravel the nature of forces which govern our material world. The topic of the ASI was chosen because it opens new vistas on this for ever new problem: the universe. Clusters of galaxies probe large-scale matter distributions and the structure of space-time.
Download or read book Fast Spectral Variability in the X ray Emission of Accreting Black Holes written by Chris Skipper and published by Springer. This book was released on 2014-09-04 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis brings together the various techniques of X-ray spectral analysis in order to examine the properties of black holes that vary in mass by several orders of magnitude. In all these systems it is widely accepted that the X-ray emission is produced by Compton up-scattering of lower energy seed photons in a hot corona or accretion flow, and here these processes are examined through a study of the X-ray spectral variability of each source. A new technique is introduced, in which models are fitted to over 2 million X-ray spectra on time-scales as short as 16 ms, and subsequently it is shown that the nature of the correlation between intensity and spectral index is strongly dependent upon the spectral state of the black hole. Finally, the results of an extensive survey of nearby galactic nuclei using the Chandra X-ray telescope are presented in the form of images and spectra, and these results are used along with data from the literature to search for Compton-thick nuclei.
Download or read book Literature 1981 Part 1 written by Siegfried Böhme and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 862 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1974-02 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Activities written by and published by . This book was released on 1979 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book N A S A Activities written by U.S. National Aeronautics and Space Administration and published by . This book was released on 1979 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt:
