English
Related papers

Related papers: Broadband microwave burst produced by electron bea…

200 papers

We investigate in detail the 21 May 2004 flare using simultaneous observations of the Nobeyama Radioheliograph, Nobeyama Radiopolarimeters, Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and Solar and Heliospheric Observatory…

Solar and Stellar Astrophysics · Physics 2015-06-19 Alexey Kuznetsov , Eduard Kontar

We present an ordinary case in the momentum diffusion equation for the electron spectrum evolution and investigate the energy spectra and time dependent properties of flare in Mrk 421 in the frame of a time-dependent one-zone synchrotron…

High Energy Astrophysical Phenomena · Physics 2016-08-02 Y. G. Zheng , S. J. Kang , J. Li

Incoherent solar radio radiation comes from the free-free, gyroresonance, and gyrosynchrotron emission mechanisms. Free-free is primarily produced from Coulomb collisions between thermal electrons and ions. Gyroresonance and gyrosynchrotron…

Solar and Stellar Astrophysics · Physics 2020-07-30 A. Nindos

Observations of gamma-ray bursts by the Fermi satellite, capable of detecting photons in a very broad energy band: 8keV to >300GeV, have opened a new window for the study of these enigmatic explosions. It is widely assumed that photons of…

High Energy Astrophysical Phenomena · Physics 2009-11-20 Pawan Kumar , Rodolfo Barniol Duran

The observed millisecond-scale duration is an essential yet mysterious feature of fast radio bursts (FRBs). In this Letter, we link the observed soft gamma-ray counterpart of FRB 200428 to electron-positron pair cascades driven by Compton…

High Energy Astrophysical Phenomena · Physics 2025-05-21 Yutong He , Christoph H. Keitel , Matteo Tamburini

Fast radio bursts (FRBs) are extragalactic, bright pulses of emission at radio frequency with milliseconds duration. Observationally, FRBs can be divided into two classes, repeating FRBs and non-repeating FRBs. At present, twenty repeating…

High Energy Astrophysical Phenomena · Physics 2020-04-22 G. Q. Zhang , S. X. Yi , F. Y. Wang

An evolution of the electron distribution function in the beam-plasma system with the return current is computed numerically for different parameters. The X-ray bremsstrahlung corresponding to such an electron distribution is calculated and…

Solar and Stellar Astrophysics · Physics 2009-12-11 M. Karlicky , J. Kasparova

We calculate the synchrotron self-Compton emission from internal shocks occurring in relativistic winds as a source of gamma-ray bursts, with allowance for self-absorption. For plausible model parameters most pulses within a Gamma-Ray Burst…

Astrophysics · Physics 2009-10-31 A. Panaitescu , P. Meszaros

Fast Radio Bursts (FRBs) are energetic millisecond radio bursts at cosmological distances, whose underlying engine is not identified. Among a sub-population that emit repeated radio bursts, a handful were associated with a persistent radio…

High Energy Astrophysical Phenomena · Physics 2025-01-27 Xian Zhang , Wenfei Yu , Zhen Yan , Yi Xing , Bing Zhang

We model the sample of fast radio bursts (FRB), including the newly discovered CHIME repeaters, using the synchrotron blast wave model of Metzger, Margalit & Sironi (2019). This model postulates that FRBs are precursor radiation from…

High Energy Astrophysical Phenomena · Physics 2020-04-29 Ben Margalit , Brian D. Metzger , Lorenzo Sironi

A leading mechanism for producing cosmological gamma-ray bursts (GRBs) is via ultra-relativistic particles in an expanding fireball. The kinetic energy of the particles is converted into thermal energy in a forward shock and a reverse…

Astrophysics · Physics 2009-10-28 Re'em Sari , Ramesh Narayan , Tsvi Piran

In the present paper a self-consistent theory, explaining shape of the observed phase-averaged radio spectrum in the frequency range from 100MHz to 10GHz is presented. The radio waves are assumed to be generated near the light cylinder…

High Energy Astrophysical Phenomena · Physics 2015-06-19 George Machabeli , Nino Chkheidze

Fast radio bursts (FRBs) are extremely strong radio flares lasting several milliseconds, most of which come from unidentified objects at a cosmological distance. They can be apparently repeating or not. In this paper, we analyzed 18…

We calculate the creation of electron--positron pairs in Gamma-Ray Bursts (GRBs) resulting from the collision between scattered and outward moving gamma-ray photons. The number of pairs exceeds the number of ambient medium electrons…

Astrophysics · Physics 2009-11-10 P. Kumar , A. Panaitescu

Shocks in the solar corona can accelerate electrons that in turn generate radio emission known as type II radio bursts. The characteristics and morphology of these radio bursts in the dynamic spectrum reflect the evolution of the shock…

Solar and Stellar Astrophysics · Physics 2025-11-19 P. Zucca , P. Zhang , K. Kozarev , M. Nedal , M. Mancini , A. Kumari , D. E. Morosan , B. Dabrowski , P. T. Gallagher , A. Krankowski , C. Vocks

Low-temperature plasma ejected in solar eruptions can screen active regions as well as quiet solar areas. Absorption phenomena can be observed in microwaves as 'negative bursts' and in different spectral domains. We analyze two very…

Solar and Stellar Astrophysics · Physics 2015-06-16 V. Grechnev , I. Kuzmenko , A. Uralov , I. Chertok , A. Kochanov

The recent discovery of a Galactic fast radio burst (FRB) occurring simultaneously with an X-ray burst (XRB) from the Galactic magnetar SGR J1935+2154 implies that at least some FRBs arise from magnetar activities. We propose that FRBs are…

High Energy Astrophysical Phenomena · Physics 2021-10-04 Yuan-Pei Yang , Bing Zhang

This paper investigates the incidence of coherent emission in solar radio bursts, using a revised catalog of 3800 solar radio bursts observed by the Nobeyama Radio Polarimeters from 1988 to 2023. We focus on the 1.0 and 2.0 GHz data, where…

Type II radio bursts are solar radio emissions generated by electrons accelerated by coronal shocks. These bursts are typically found close to expanding coronal mass ejections (CMEs), making them valuable for studying the properties and…

Solar and Stellar Astrophysics · Physics 2026-05-13 K. Bhandari , D. E. Morosan , S. Normo

We present a high fidelity snapshot spectroscopic radio imaging study of a weak type I solar noise storm which took place during an otherwise exceptionally quiet time. Using high fidelity images from the Murchison Widefield Array, we track…

Solar and Stellar Astrophysics · Physics 2021-10-13 Surajit Mondal , Divya Oberoi