Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C. PDF Download

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 18

View

Book Description

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

View

Book Description
Fermi Gamma-ray telescope data of GRB 080916C with ~10(55) erg in apparent isotropic Gamma-ray energy, show a several second delay between the rise of 100 MeV-GeV radiation compared with keV-MeV radiation. Here we show that synchrotron radiation from cosmic ray protons accelerated in GRBs, delayed by the proton synchrotron cooling timescale in a jet of magnetically-dominated shocked plasma moving at highly relativistic speeds with bulk Lorentz factor could explain this result. A second generation electron synchrotron component from attenuated proton synchrotron radiation makes enhanced soft X-ray to MeV Gamma-ray emission. Long GRBs with narrow, energetic jets accelerating particles to ultra-high energies could explain the Auger observations of UHE cosmic rays from sources within 100 Mpc for nano-Gauss intergalactic magnetic fields. The total energy requirements in a proton synchrotron model are Gamma-16/3.

Author: Aurélien Philippe Bouvier
Publisher:
ISBN:
Category :
Languages : en
Pages :

View

Book Description
The Fermi Gamma-ray Space Telescope recently celebrated its two-years anniversary in space. With the Large Area Telescope (LAT), its main instrument onboard, Fermi opened a new era in high-energy astrophysics and in particular for the study of Gamma-Ray Bursts (GRBs), which are short flashes of -rays associated with the brightest and most distant events ever observed in our universe after the Big Bang. My thesis work focused primarily on the observations of this phenomenon with the LAT (20 MeV - 300 GeV) and the Gamma-ray Burst Monitor (10 keV - 40 MeV) onboard the Fermi satellite. After describing the procedure used for detection and analysis of LAT GRBs, I will provide an overview of the temporal and spectral features observed during the prompt emission of these events after one year and a half of operation for Fermi. GRBs can also be used as a tool to probe interesting physics. My focus will be on the detection of very high energy photons (typically above 10 GeV) associated with LAT GRBs and which were used to set significant constraints both on a possible violation of Lorentz invariance - which postulates that all observers measure exactly the same speed of light in vacuum, independently of photon energy - and on the Optical-Ultraviolet extragalactic background light in the Universe.

Author: Remo Ruffini
Publisher: World Scientific
ISBN: 9811269785
Category : Science
Languages : en
Pages : 4880

View

Book Description
The proceedings of MG16 give a broad view of all aspects of gravitational physics and astrophysics, from mathematical issues to recent observations and experiments. The scientific program of the meeting included 46 plenary presentations, 3 public lectures, 5 round tables and 81 parallel sessions arranged during the intense six-day online meeting. All talks were recorded and are available on the ICRANet YouTube channel at the following link: www.icranet.org/video_mg16.These proceedings are a representative sample of the very many contributions made at the meeting. They contain 383 papers, among which 14 come from the plenary sessions.The material represented in these proceedings cover the following topics: accretion, active galactic nuclei, alternative theories of gravity, black holes (theory, observations and experiments), binaries, boson stars, cosmic microwave background, cosmic strings, dark energy and large scale structure, dark matter, education, exact solutions, early universe, fundamental interactions and stellar evolution, fast transients, gravitational waves, high energy physics, history of relativity, neutron stars, precision tests, quantum gravity, strong fields, and white dwarf; all of them represented by a large number of contributions.The online e-proceedings are published in an open access format.

Author: Gilbert Vedrenne
Publisher: Springer Science & Business Media
ISBN: 354039088X
Category : Science
Languages : en
Pages : 613

View

Book Description
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.

Author: Bing Zhang
Publisher: Cambridge University Press
ISBN: 1107027616
Category : History
Languages : en
Pages : 617

View

Book Description
A complete text on the physics of gamma-ray bursts, the most brilliant explosions since the Big Bang.

Author: Ahmed M. Maghraby
Publisher: BoD – Books on Demand
ISBN: 9535131613
Category : Science
Languages : en
Pages : 226

View

Book Description
Gamma radiation has been discovered since more than a century and contributed in many achievements in human life. Continuous developments make it necessary to have more understandings and more discussions about well-established concepts as well as newly implemented hypothesis and applications of gamma rays. This book presents new visions of gamma ray spectrometry and applications. I hope this book can present part of the useful applications of gamma rays.

Author: Space Telescope Science Institute (U.S.). Symposium
Publisher: Cambridge University Press
ISBN: 9780521630979
Category : Science
Languages : en
Pages : 328

View

Book Description
The Hubble Deep Field (HDF) is the deepest optical image of the Universe ever obtained. It is the result of a 150-orbit observing programme with the Hubble Space Telescope. It provides a unique resource for researchers studying the formation and evolution of stars and galaxies. This timely volume provides the first comprehensive overview of the HDF and its scientific impact on our understanding in cosmology. It presents articles by a host of world experts who gathered together at an international conference at the Space Telescope Science Institute. The contributions combine observations of the HDF at a variety of wavelengths with the latest theoretical progress in our understanding of the cosmic history of star and galaxy formation. The HDF is set to revolutionize our understanding in cosmology. This book therefore provides an indispensable reference for all graduate students and researchers in observational or theoretical cosmology.

Author: Martin C. E. Huber
Publisher: Springer Science & Business Media
ISBN: 1461478049
Category : Science
Languages : en
Pages : 726

View

Book Description
An ideal resource for lecturers, this book provides a comprehensive review of experimental space astronomy. The number of astronomers whose knowledge and interest is concentrated on interpreting observations has grown substantially in the past decades; yet, the number of scientists who are familiar with and capable of dealing with instrumentation has dwindled. All of the authors of this work are leading and experienced experts and practitioners who have designed, built, tested, calibrated, launched and operated advanced observing equipment for space astronomy. This book also contains concise information on the history of the field, supported by appropriate references. Moreover, scientists working in other fields will be able to get a quick overview of the salient issues of observing photons in any one of the various energy, wavelength and frequency ranges accessible in space. This book was written with the intention to make it accessible to advanced undergraduate and graduate students.