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Related papers: Spectral Modeling of GRB Pulses

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We discuss the prompt emission of GRBs, allowing for $\gamma\gamma$ pair production and synchrotron self-absorption. The observed hard spectra suggest heavy pair-loading in GRBs. The re-emission of the generated pairs results in the energy…

Astrophysics · Physics 2009-11-10 Zhuo Li , Li-Ming Song

The discovery (Liang & Kargatis 1996), that the peak energy of time-resolved spectra of gamma-ray burst (GRB) pulses decays exponentially with fluence, is analytically shown to imply that the time-integrated photon number spectrum of a…

Astrophysics · Physics 2009-10-30 Felix Ryde , Roland Svensson

We investigate the dynamics and radiation from a relativistic blast-wave which decelerates as it sweeps up ambient matter. The bulk kinetic energy of the blast-wave shell is converted into internal energy by the process of accreting…

Astrophysics · Physics 2016-08-30 J. Chiang , C. D. Dermer

We propose a model for the spectral formation of Gamma Ray Burst (GRB) prompt emission, where the phenomenological Band's function is usually applied to describe the GRB prompt emission. We suggest that the GRB prompt emission is mainly a…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Lev Titarchuk , Ruben Farinelli , Filippo Frontera , Lorenzo Amati

This work is a continuation of a previous effort (Panaitescu 2019) to study the cooling of relativistic electrons through radiation (synchrotron and self-Compton) emission and adiabatic losses, with application to the spectra and…

High Energy Astrophysical Phenomena · Physics 2022-10-26 A. D. Panaitescu , W. T. Vestrand

Synchrotron self-Compton (SSC) scattering is an important emission mechanism in many astronomical sources, such as gamma-ray bursts (GRBs) and active galactic nuclei (AGNs). We give a complete presentation of the analytical approximations…

High Energy Astrophysical Phenomena · Physics 2015-06-04 He Gao , Wei-Hua Lei , Xue-Feng Wu , Bing Zhang

We investigate synchrotron emission models as the source of gamma ray burst spectra. We show that allowing for synchrotron self absorption and a ``smooth cutoff'' to the electron energy distribution produces a wide range of low energy…

Astrophysics · Physics 2018-11-06 Nicole M. Lloyd-Ronning , Vahe' Petrosian

Many classes of gamma-ray sources, such as gamma-ray bursts, blazars, Seyfert galaxies, and galactic black hole sources are surrounded by large amounts of gas and dust. X-rays and gamma-rays that traverse this material will be attenuated by…

Astrophysics · Physics 2007-05-23 C. D. Dermer , M. Boettcher , E. P. Liang

The evolution of a dilute electron-positron fireball is calculated in the regime of strong magnetization and very high compactness (l ~10^3-10^8). Heating is applied at a low effective temperature (< 25 keV), and the fireball is allowed to…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Christopher Thompson , Ramandeep Gill

The prompt emission from GRBs is the brightest electromagnetic emission known yet it's origin is not understood. The flux density of individual prompt pulses of a GRB can be represented by an analytical expression derived assuming the…

High Energy Astrophysical Phenomena · Physics 2015-05-14 R. Willingale , F. Genet , J. Granot , P. T. O'Brien

Sari, Piran, and Narayan have derived analytic formulas to model the spectra from gamma-ray burst blast waves that are energized by sweeping up material from the surrounding medium. We extend these expressions to apply to general radiative…

Astrophysics · Physics 2009-10-31 C. D. Dermer , M. Boettcher , J. Chiang

A small fraction of X-ray photons from gamma-ray bursts (GRBs), after escaping the relativistic jet, are scattered by electrons in the circumburst medium. Subsequent photon-photon absorption between the incoming MeV $\gamma$-rays and the…

A simple mathematical model of GRB pulses in time, suggested in Norris et al. (2005), is extended across energy. For a class of isolated pulses, two of those parameters appear effectively independent of energy. Specifically, statistical…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Robert J. Nemiroff

In order to better understand the physical origin of short duration gamma-ray bursts (GRBs), we perform time-resolved spectral analysis on a sample of 70 pulses in 68 short GRBs with burst duration $T_{90}\lesssim2$ s detected by the…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Hüsne Dereli-Bégué , Asaf Pe'er , Felix Ryde

We discuss non-thermal emission mechanism of the Crab-like pulsars with both a two-dimensional electrodynamical study and a three-dimensional model. We investigate the emission process in the outer gap accelerator. In the two-dimensional…

Astrophysics · Physics 2009-11-13 J. Takata , H. -K. Chang

We propose a backscattering dominated prompt emission model for gamma-ray bursts (GRB) prompt phase in which the photons generated through pair annihilation at the centre of the burst are backscattered through Compton scattering by an…

High Energy Astrophysical Phenomena · Physics 2021-11-30 Mukesh Kumar Vyas , Asaf Pe'er , David Eichler

A substantial fraction of prompt GRB spectra have soft spectral indexes exceeding the maximum allowed by the synchrotron model alpha_{max}=-2/3. Some spectra also exhibit very sharp break at E_p, inconsistent with the smooth synchrotron…

Astrophysics · Physics 2009-11-10 Mikhail V. Medvedev

X-ray emission can provide a crucial diagnostic of gamma-ray bursts (GRBs). We calculate the X-ray and gamma-ray spectra of impulsive acceleration episodes related to GRB pulses. We use the synchrotron shock model (SSM) as a basis of our…

Astrophysics · Physics 2009-10-28 M. Tavani

Recently proposed correlations between the energetics of Gamma-Ray Bursts (GRB) and their spectral properties, namely the peak energy of their prompt emission, are found to account for the observed fluence distribution of all `bright' BATSE…

Astrophysics · Physics 2007-05-23 Z. Bosnjak , A. Celotti , F. Longo , G. Barbiellini

Isolated Swift gamma-ray burst (GRB) pulses, like their higher-energy BATSE counterparts, emit the bulk of their pulsed emission as a hard-to-soft component that can be fitted by the Norris et al. (2005) empirical pulse model. This signal…

High Energy Astrophysical Phenomena · Physics 2016-01-20 Jon Hakkila , Amy Lien , Takanori Sakamoto , David Morris , James E. Neff , Timothy W. Giblin