scholarly journals Compton-driven beam formation and magnetization via plasma microinstabilities

2021 ◽  
Vol 87 (3) ◽  
Author(s):  
Bertrand Martinez ◽  
Thomas Grismayer ◽  
Luís O. Silva
Keyword(s):  
Gamma Rays ◽  
Gamma Ray ◽  
Magnetic Energy ◽  
Positron Beam ◽  
Gamma Ray Bursts ◽  
Particle In Cell ◽  
Pair Plasma ◽  
Electron Positron ◽  
Beam Formation ◽  
Beam Plasma Instability

Compton scattering of gamma rays propagating in a pair plasma can drive the formation of a relativistic electron positron beam. This process is scrutinized theoretically and numerically via particle-in-cell simulations. In addition, we determine in which conditions the beam can prompt a beam-plasma instability and convert its kinetic energy into magnetic energy. We argue that such conditions can be met at the photosphere radius of bright gamma-ray bursts.

scholarly journals Optical Afterglows as Probes for the Central Engine and Fireball of Gamma-Ray Bursts

2012 ◽  
Vol 8 (S290) ◽  
pp. 263-264
Author(s):  
Liang Li ◽  
En-Wei Liang ◽  
He Gao ◽  
Bing Zhang
Keyword(s):  
Statistical Analysis ◽  
Gamma Rays ◽  
Density Profile ◽  
Gamma Ray ◽  
Ambient Medium ◽  
Gamma Ray Bursts ◽  
Prompt Gamma ◽  
Medium Density ◽  
Central Engine ◽  
Prompt Emission

AbstractWell-sampled optical lightcurves of 146 gamma-ray bursts (GRBs) are compiled from literature. We identify possible emission components based on our empirical fits and present statistical analysis for these components. We find that the flares are related to prompt emission, suggesting that they could have the same origin in different episodes. The shallow decay segment is not correlated with prompt gamma-rays. It likely signals a long-lasting injected wind from GRB central engines. Early after onset peak is closely related with prompt emission. The ambient medium density profile is likely n ∝ r−1. No correlation between the late re-brightening bump and prompt gamma-rays or the onset bump is found. They may be from another jet component.

GAMMA-RAY BURSTS AS VHE-UHE SOURCES

2008 ◽  
Vol 17 (09) ◽  
pp. 1319-1332
Author(s):  
PETER MÉSZÁROS
Keyword(s):  
Cosmic Rays ◽  
Gamma Rays ◽  
Lower Energy ◽  
Gamma Ray ◽  
Gamma Ray Bursts ◽  
Model Parameters ◽  
Fundamental Interaction ◽  
Acceleration Mechanism ◽  
Inverse Compton ◽  
Tev Gamma Rays

Gamma-ray bursts are capable of accelerating cosmic rays up to GZK energies Ep ~ 1020 eV, which can lead to a flux at Earth comparable to that observed by large EAS arrays such as Auger. The semi-relativistic outflows inferred in GRB-related hypernovae are also likely sources of somewhat lower energy cosmic rays. Leptonic processes, such as synchrotron and inverse Compton, as well as hadronic processes, can lead to GeV-TeV gamma-rays measurable by GLAST, AGILE, or ACTs, providing useful probes of the burst physics and model parameters. Photo-meson interactions also produce neutrinos at energies ranging from sub-TeV to EeV, which will be probed with forthcoming experiments such as IceCube, ANITA and KM3NeT. This would provide information about the fundamental interaction physics, the acceleration mechanism, the nature of the sources and their environment.

scholarly journals Diverse Features of the Multiwavelength Afterglows of Gamma-Ray Bursts: Natural or Special?

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
J. J. Geng ◽  
Y. F. Huang
Keyword(s):  
Black Holes ◽  
Numerical Method ◽  
Gamma Ray ◽  
Gamma Ray Bursts ◽  
Shock Model ◽  
Reverse Shock ◽  
X Ray ◽  
Electron Positron ◽  
Forward Shock ◽  
Electron Positron Pair

The detection of optical rebrightenings and X-ray plateaus in the afterglows of gamma-ray bursts (GRBs) challenges the generic external shock model. Recently, we have developed a numerical method to calculate the dynamics of the system consisting of a forward shock and a reverse shock. Here, we briefly review the applications of this method in the afterglow theory. By relating these diverse features to the central engines of GRBs, we find that the steep optical rebrightenings would be caused by the fall-back accretion of black holes, while the shallow optical rebrightenings are the consequence of the injection of the electron-positron-pair wind from the central magnetar. These studies provide useful ways to probe the characteristics of GRB central engines.

scholarly journals INTERNAL ENERGY DISSIPATION OF GAMMA-RAY BURSTS OBSERVED WITHSWIFT: PRECURSORS, PROMPT GAMMA-RAYS, EXTENDED EMISSION, AND LATE X-RAY FLARES

2014 ◽  
Vol 789 (2) ◽  
pp. 145 ◽  
Author(s):  
You-Dong Hu ◽  
En-Wei Liang ◽  
Shao-Qiang Xi ◽  
Fang-Kun Peng ◽  
Rui-Jing Lu ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Internal Energy ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Gamma Ray Bursts ◽  
Prompt Gamma ◽  
X Ray ◽  
Extended Emission

scholarly journals Modes of Energy Loss from Isolated Magnetized Neutron Star

1987 ◽  
Vol 125 ◽  
pp. 450-450
Author(s):  
S. Shibata
Keyword(s):  
Magnetic Field ◽  
Neutron Star ◽  
Gamma Ray ◽  
Rotational Energy ◽  
Pair Creation ◽  
Dipole Radiation ◽  
Pair Plasma ◽  
Electron Positron ◽  
Closed Current ◽  
Electron Positron Pair

Pulsar may be regarded as a discharge tube by electron-positron pair creation. On this viewpoint we carry out two numerical calculations. The obtained magnetic field is consistent with the flow. We find that pulsars emit their rotational energy through three modes simultaneously. The three modes are (1)relativistic acceleration and following gamma-ray emission in the closed current circuit in the magnetosphere, (2)wind of the electron-positron pair plasma, and (3)dipole radiation.

scholarly journals Gamma-Ray Burst Observations with BATSE

1998 ◽  
Vol 188 ◽  
pp. 159-162
Author(s):  
Gerald J. Fishman
Keyword(s):  
Gamma Rays ◽  
Gamma Ray ◽  
Gamma Ray Bursts ◽  
Gamma Ray Burst ◽  
New Era ◽  
X Ray ◽  
Time Profiles ◽  
Random Direction ◽  
Wide Range ◽  
New Phenomena

Gamma-ray bursts (GRBs) will be recorded as one of the outstanding new phenomena discovered in astronomy this century. About once per day, a burst of gamma rays appears from a random direction on the sky. Often, the burst outshines all other sources of gamma-rays in the sky, combined. This paper reviews some of the key observed phenomenon of bursts in the hard x-ray/gamma-ray region, as observed with the BATSE experiment on the Compton Gamma Ray Observatory. The observed time profiles, spectral properties and durations of gamma-ray bursts cover a wide range. Recent breakthroughs in the observation of gamma-ray burst counterparts and afterglows in other wavelength regions have marked the beginning of a new era in gamma-ray burst research. Those observations are described in following papers in these proceedings.

scholarly journals Acceleration Processes for Gamma-Ray Bursts

1994 ◽  
Vol 142 ◽  
pp. 869-876 ◽  
Author(s):  
Igor G. Mitrofanov
Keyword(s):  
Particle Acceleration ◽  
Electric Field ◽  
Neutron Stars ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Initial Energy ◽  
Gamma Ray Bursts ◽  
Acceleration Of Particles ◽  
Radiation Mechanisms ◽  
Radiative Pressure

AbstractIs it shown that for those astronomical models of cosmic gamma-ray bursts (GRBs) which are associated with galactic neutron stars (NSs), the initial energy of the outburst could be converted to gamma-rays through processes of particle acceleration. The main emission mechanisms are considered for two basic alternatives, when particles are accelerated either by radiative pressure or by an electric field.Subject headings: acceleration of particles — gamma rays: bursts — radiation mechanisms: nonthermal

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