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Related papers: GLAST, GRBs, and Quantum Gravity

200 papers

We summarize our model for long-duration gamma ray bursts (GRBs) that fits the redshift (z) distributions measured with Swift and missions before Swift, and the pre-Swift GRB jet opening-angle distribution inferred from achromatic breaks in…

Astrophysics · Physics 2008-11-26 Truong Le , Charles D. Dermer

Gamma-ray bursts (GRBs) are luminous enough to be detectable up to redshift $z\sim 10$. They are often proposed as complementary tools to type-Ia supernovae (SNe Ia) in tracing the Hubble diagram of the Universe. The distance calibrations…

General Relativity and Quantum Cosmology · Physics 2015-11-30 Hai-Nan Lin , Xin Li , Zhe Chang

Analyzing data from GLAST's Large Area Telescope (LAT) will require sophisticated techniques. The PSF and effective area are functions of both photon energy and the position in the field-of-view. During most of the mission the observatory…

Astrophysics · Physics 2009-11-10 David L. Band , Seth W. Digel , the GLAST LAT Collaboration , the GSSC

The effect of Quantum Gravity (QG) may bring a tiny light speed variation as $v(E)=c(1-E/E_{\rm LV})$, where $E$ is the photon energy and $E_{\rm LV}$ is a Lorentz violation scale. A remarkable regularity was suggested in previous studies…

General Relativity and Quantum Cosmology · Physics 2018-02-07 Haowei Xu , Bo-Qiang Ma

The Gamma-ray Large Area Space Telescope (GLAST) is an observatory designed to perform gamma-ray astronomy in the energy range 20 MeV to 300 GeV, with supporting measurements for gamma-ray bursts from 10 keV to 25 MeV. GLAST will be…

Astrophysics · Physics 2009-06-23 D. Paneque , A. Borgland , A. Bovier , E. Bloom , Y. Edmonds , S. Funk , G. Godfrey , R. Rando , L. Wai , P. Wang

We use a homogeneous sample of gamma-ray bursts (GRB) extracted from 5.9 years of BATSE DISCLA data (astro-ph/9908190) and a variety of broken power-law luminosity functions to derive GRB luminosities and space densities. Luminosity…

Astrophysics · Physics 2009-10-31 Maarten Schmidt

We discuss several constraints on the properties of gamma-ray bursts (GRB) at cosmological distances. First we use the requirement that burst sources must be optically thin to pair production by photon-photon collisions in order to produce…

Astrophysics · Physics 2009-10-28 Eric Woods , Abraham Loeb

Gamma rays at rest frame energies as high as 90 GeV have been reported from gamma-ray bursts (GRBs) by the Fermi Large Area Telescope (LAT). There is considerable hope that a confirmed GRB detection will be possible with the upcoming…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Rudy C. Gilmore , Aurelien Bouvier , Valerie Connaughton , Adam Goldstein , Nepomuk Otte , Joel R. Primack , David A. Williams

High-energy gamma rays are a valuable tool for studying particle acceleration and radiation in the magnetospheres of energetic pulsars. The six or more pulsars seen by CGRO/EGRET show that: the light curves usually have double-peak…

Astrophysics · Physics 2009-11-06 David J. Thompson

It is often stated that gamma-ray bursts (GRBs) have typical energies of several hundred keV. Is this a real feature of GRBs or is it due to an observational bias? We consider the possibility that bursts of a given bolometric luminosity…

Astrophysics · Physics 2009-10-28 Tsvi Piran , Ramesh Narayan

Gamma-ray bursts (GRBs) can be probes of the early universe, but currently, only 26% of GRBs observed by the Neil Gehrels Swift Observatory GRBs have known redshifts ($z$) due to observational limitations. To address this, we estimated the…

Observations of high energy emission from gamma-ray bursts (GRBs) constrain the extreme physical conditions associated with these energetic cosmic explosions. The Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope, a…

High Energy Astrophysical Phenomena · Physics 2009-12-17 S. B. Pandey , Carl W. Akerlof , W. Zheng , F. Yuan

A recent spectrum of the optical afterglow of GRB 970508 suggests that gamma-ray bursts (GRBs) are cosmological in origin and it is of crucial importance to derive an accurate distance to each burst. If GRBs occur near their host galaxies…

Gamma-ray bursts (GRBs) are among the most potent probes of Lorentz invariance violation (LIV), offering direct constraints on the quantum gravity energy scale ($E_{\rm QG}$) based on observations of energy-dependent time lags. Individual…

High Energy Astrophysical Phenomena · Physics 2025-12-30 Shen-Shi Du , Yi Gong , Jun-Jie Wei , Zi-Ke Liu , Zhi-Qiang You , Yan-Zhi Meng , Xing-Jiang Zhu

The study of time lags between spikes in Gamma-Ray Burst light curves in different energy bands as a function of redshift may lead to the detection of effects due to Quantum Gravity. We present an analysis of 15 Gamma-Ray Bursts with…

Astrophysics · Physics 2008-11-26 J. Bolmont , J. -L. Atteia , A. Jacholkowska , F. Piron , G. Pizzichini

In order to test the efficacy of Gamma-ray Bursts (GRB) as cosmological probes, we characterize the scatter in the correlations between six pairs of GRB observables, which have previously also been studied in arXiv:2011.14040. However, some…

High Energy Astrophysical Phenomena · Physics 2024-10-28 Sarveshkumar Purohit , Shantanu Desai

The first Gamma-Ray Burst (GRB) catalog presented by the Fermi-Large Area Telescope (LAT) collaboration includes 28 GRBs, detected above 100 MeV over the first three years since the launch of the Fermi mission. However, more than 100 GRBs…

High Energy Astrophysical Phenomena · Physics 2015-09-07 Elisabetta Bissaldi , Tristano Di Girolamo , Francesco Longo , Piero Vallania , Carlo Vigorito

In three years of observations since the beginning of nominal science operations in August 2008, the Large Area Telescope (LAT) on board the Fermi Gamma Ray Space Telescope has observed high-energy (>20 MeV) \gamma-ray emission from 35…

High Energy Astrophysical Phenomena · Physics 2015-06-15 LAT Collaboration

Gamma-ray bursts (GRBs) are the most powerful electromagnetic outbursts in the Universe and emit a vast amount of their energy in the form of gamma rays. Their duration is extremely short on cosmic timescales, but they show a wealth of time…

High Energy Astrophysical Phenomena · Physics 2025-12-11 Else Magnus , Jannes Loonen , Rose S. Stanley , Paul Coppin , Krijn D. de Vries , Nick van Eijndhoven

Gamma Ray Bursts (GRBs) are among the most powerful sources in the Universe: they emit up to 10^54 erg in the hard X-ray band in few tens of seconds. The cosmological origin of GRBs has been confirmed by several spectroscopic measurements…

Astrophysics · Physics 2011-07-19 G. Ghirlanda , G. Ghisellini , C. Firmani