Download or read book OSSE Observations of Positron Annihilation in the Galactic Plane written by and published by . This book was released on 1996 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: OSSE has measured the galactic longitude distribution of both the 511 keV annihilation line radiation and the three-photon positronium continuum within ~40 degrees of the center. They have similar shapes, with a composite longitude distribution well represented by an ~11 degrees FWHM Gaussian central bulge together with a possible broad disk component comprising as much as 15% of the integral flux between 40 degrees and 320 degrees longitude. Contributions from one or more discrete source(s) at or near the center with total annihilation radiation (line plus continuum) intensities of up to ~4 x 10(exp -4) photons cu cm sec(exp -1) (2 sigma upper limit) are compatible with the observed distribution. The best estimate of the positronium fraction is 0.97 plus or minus 0.03. No evidence for variation in the positronium fraction is observed.
Download or read book OSSE Observations of Galactic 511 KeV Positron Annihilation Radiation Initial Phase 1 Results written by and published by . This book was released on 1993 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Oriented Scintillation Spectrometer Experiment (OSSE) on the Compton Gamma-Ray Observatory (GRO) has performed numerous observations of the galactic plane and galactic center region to measure the distribution of galactic 511 keV positron annihilation radiation and to search for time variability of the emission; the initial 511 keV line fluxes for the observations performed during the first 18 months of the GRO mission are presented. The 511 keV line flux for a typical galactic center observation is (2:5 plus or minus 0:3) x 10(exp -1) gamma sq cm s(exp -1), where the quoted uncertainty represents the 1 sigma statistical uncertainty. No statistically significant time variability of the line flux has been observed; the 3 sigma upper linit to daily variations from the mean is 3 x 10(exp -4) gamma sq cm s(exp -1). The distribution of galactic 511 keV positron annihilation radiation implied by the OSSE observations is discussed and compared with observations by other instruments.
Download or read book OSSE Observations of Galactic 511 KeV Annihilation Radiation written by and published by . This book was released on 1991 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Oriented Scintillation Spectrometer Experiment (OSSE) on the Compton Gamma-Ray Observatory has performed several observations of the Galactic plane and Galactic center region to measure the distribution of Galactic 511 keV positron annihilation radiation. Preliminary analysis of data collected during the observation of the Galactic center region over the period July 13[24, 1991, indicates the presence of a 511 keV line and positronium continuum superimposed on a power-law continuum.
Download or read book Observations of Galactic Positron Annihilation Radiation written by Michael S. Briggs and published by . This book was released on 1991 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Distribution of Galactic 511 KeV Positron Annihilation Radiation written by and published by . This book was released on 1994 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Oriented Scintillation Spectrometer Experiment (OSSE) on NASA's Compton Gamma-Ray Observatory has completed numerous observations of the Galactic plane and Galactic center region. A principle objective of these observations was to measure the distribution of the Galactic positron annihilation radiation. Most of these observations provided positive detections of the narrow 511 keV annihilation line. These data were fitted using several diffuse distribution models representing various populations of progenitor objects. The only model investigated which is not rejected is a two-component distribution consisting of spheroidal and disk components; all other models investigated can be rejected at the> 4:5 sigma confidence level. The size of the spheroidal component is found to be
Download or read book Current Topics In Astrofundamental Physics Proceedings Of The 2nd Course In The International School Of Astrophysics D Chalonge written by Normalized Sanchez and published by World Scientific. This book was released on 1993-08-27 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an updated understanding of the progress and current problems in the interplay between fundamental physics, astrophysics and cosmology.
Download or read book The Gamma Ray Sky with Compton GRO and SIGMA written by M. Signore and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume consists of invited lectures and seminars presented at the NATO Advanced Study Institute "The Gamma Ray Sky with COMPTON GRO and SIGMA" , which was held at the Centre de Physique Theorique of Les Houches (France) in January / February 1994. The school has been planned by a Scientific Organizing Committee. It was organized with the aim of providing students and young researchers with an up-to-date account of the high-energy phenomena in the vicinity of compact objets and the diffuse gamma-ray backgrounds after the early results from the gamma-ray telescope SIGMA and the four instruments onboard COMPTON GRO (Gamma Ray Observatory) : BATSE (Burst and Transient Source Experiment),COMPTEL(Compto'l Telescope),EGRET (Energetic Gamma Ray Experiment Telescope) and OS SE(Oriented Scintillation Spectrometer Experiment) . It was attended by more than sixty researchers from many countries. The lectures and seminars represent a complete coverage of our present knowledge and understanding of: Gamma-ray backgrounds, Gamma-ray Burts,Active Galactic Nuclei,Galactic Compact Objects, Gamma-ray Spectroscopy, Instrumentation and observation techniques, etc ... Most of these lectures are reproduced in this volume. Unfortunately, a few lecturers have chosen not to submit their manuscript.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 1572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Energy Astrophysics Models And Observations From Mev To Tev written by Peter L Biermann and published by World Scientific. This book was released on 1994-06-21 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a collection of comprehensive reviews on astrophysics at the highest energies. It puts together, for the first time, discussions of astrophysics from MeV to EeV energies and beyond. Observations at these energies reveal nuclear and particle physics throughout our galaxy as well as in the most extreme environments in the entire cosmos. These reports range from the recent spectacular results from the Compton Gamma Ray Observatory, including the latest information on enigmatic gamma ray bursts, to cosmic rays at the highest energies ever observed by man.
Download or read book High Energy Astrophysics written by James Matthews and published by World Scientific. This book was released on 1994 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a collection of comprehensive reviews on astrophysics at the highest energies. It puts together, for the first time, discussions of astrophysics from MeV to EeV energies and beyond. Observations at these energies reveal nuclear and particle physics throughout our galaxy as well as in the most extreme environments in the entire cosmos. These reports range from the recent spectacular results from the Compton Gamma Ray Observatory, including the latest information on enigmatic gamma ray bursts, to cosmic rays at the highest energies ever observed by man.
Download or read book Reports on Astronomy written by Immo Appenzeller and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: IAU Transactions are published as a volume corresponding to each General Assembly. Volume A is produced prior to the Assembly and contains Reports on Astronomy, prepared by each Commission President. The intention is to summarize the astronomical results that have affected the work of the Commission since the production of the previous Reports up to a time which is about one year prior to the General Assembly. Volume B is produced after the Assembly and contains accounts of Commission Meetings which were held, together with other material. The reports included in the present volume range from outline summaries to lengthy compilations and references. Most reports are in English.
Download or read book The Second Compton Symposium written by N. Gehrels and published by American Inst. of Physics. This book was released on 1998-03-19 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Proceedings of a conference held in College Park, Maryland, in September 1993. Papers discuss results from the Compton Gamma Ray Observatory, in orbit since 1991. Presentations are divided into sections on opening remarks, spin-powered pulsars, nucleosynthesis, galactic sources, galactic center, cosmic rays and galactic diffusion radiation, agn-seyferts, agn-quasars and bl lacs, and analysis and instrumentation. No index. Annotation c. by Book News, Inc., Portland, Or.
Download or read book Solar Stellar and Galactic Connections between Particle Physics and Astrophysics written by Alberto Carramiñana and published by Springer Science & Business Media. This book was released on 2007-03-23 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book collects extended and specialized reviews on topics linking astrophysics and particle physics at a level between a graduate student and a young researcher. The book also includes three reviews on observational techniques used in forefront astrophysics and short articles on research performed in Latin America. The reviews, updated and written by specialized researchers, describe the state of the art in the related research topics.
Download or read book The Compton Observatory Science Workshop written by Chris R. Shrader and published by . This book was released on 1992 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Gamma Ray Observatory Science Workshop written by W. Neil Johnson and published by . This book was released on 1989 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Astronomy with Radioactivities written by Roland Diehl and published by Springer Science & Business Media. This book was released on 2010-10-02 with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the reader to the field of nuclear astrophysics, i.e. the acquisition and reading of measurements on unstable isotopes in different parts of the universe. The authors explain the role of radioactivities in astrophysics, discuss specific sources of cosmic isotopes and in which special regions they can be observed. More specifically, the authors address stars of different types, stellar explosions which terminate stellar evolutions, and other explosions triggered by mass transfers and instabilities in binary stars. They also address nuclear reactions and transport processes in interstellar space, in the contexts of cosmic rays and of chemical evolution. A special chapter is dedicated to the solar system which even provides material samples. The book also contains a description of key tools which astrophysicists employ in those particular studies and a glossary of key terms in astronomy with radioactivities.
Download or read book Reports on Astronomy written by Jacqueline Bergeron and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 603 pages. Available in PDF, EPUB and Kindle. Book excerpt: IAU Transactions are published as a volume corresponding to each General Assembly. Volume A is produced prior to the Assembly and contains Reports on Astronomy, prepared by each Commission President. The intention is to summarize the astronomical results that have affected the work of the Commission since the production of the previous Reports up to a time which is about one year prior to the General Assembly. Volume B is produced after the Assembly and contains accounts of Commission Meetings which were held, together with other material. The reports included in the present volume range from outline summaries to lengthy compilations and references. Most reports are in English.
