English
Related papers

Related papers: Gamma-ray emission of hot astrophysical plasmas

200 papers

De-excitation gamma-ray lines, produced by nuclei colliding with protons, provide information about astrophysical environments where particles have kinetic energies of $10-100$ MeV per nucleon. In general, such environments can be…

High Energy Astrophysical Phenomena · Physics 2023-09-12 Hiroki Yoneda , Felix Aharonian , Paolo Coppi , Thomas Siegert , Tadayuki Takahashi

This chapter is intended to provide a general presentation of the atomic and nuclear processes responsible for X-ray line and gamma-ray line emission in various astrophysical environments. I consider line production from hot plasmas, from…

Astrophysics · Physics 2015-06-24 Vincent Tatischeff

The importance of nuclear reactions in low-density astrophysical plasmas with ion temperatures $T \geq 10^{10}$ K has been recognized for more than thirty years. However, the lack of comprehensive data banks of relevant nuclear reactions…

Solar and Stellar Astrophysics · Physics 2012-02-15 Ervin Kafexhiu , Felix Aharonian , Gabriela Vila

In this paper we model the emission from a relativistically expanding electron-positron pair plasma fireball originating near the surface of a heated neutron star. This pair fireball is deposited via the annihilation of neutrino pairs…

Astrophysics · Physics 2009-10-31 Jay D. Salmonson , James R. Wilson , Grant J. Mathews

We present some recent highlights and prospects for the study of hot astrophysical plasmas. Hot plasmas can be studied primarily through their X-ray emission and absorption. Most astrophysical objects, from solar system objects to the…

High Energy Astrophysical Phenomena · Physics 2017-09-13 J. S. Kaastra , L. Gu , J. Mao , M. Mehdipour , F. Mernier , J. de Plaa , A. J. J. Raassen , I. Urdampilleta

Optically thin accretion plasmas can reach ion temperatures $T_{\rm i} \geq 10^{10}$K and thus trigger nuclear reactions. Using a large nuclear interactions network, we studied the radial evolution of the chemical composition of the…

High Energy Astrophysical Phenomena · Physics 2019-04-03 Ervin Kafexhiu , Felix Aharonian , Maxim Barkov

K-line profiles emitted from a warm dense plasma environment are used for diagnostics of Ar droplet plasmas created by high energy laser pulses. Analyzing the temporally and spacially integrated spectra, we infer temperature gradients…

Plasma Physics · Physics 2017-09-26 A Sengebusch , H Reinholz , G Röpke

Large-voltage and high-temperature plasma columns produced by pinch discharge can generate gamma-ray flashes with energy spectra and spectral evolution consistent with that observed in gamma-ray bursts (GRBs). The inverse Compton scattering…

Astrophysics · Physics 2014-10-13 Mei Wu , Li Chen , Ti-pei Li

Recent radio observations support a picture for star formation where there is accretion of matter onto a central protostar with the ejection of molecular outflows that can affect the surrounding medium. The impact of a supersonic outflow on…

Astrophysics · Physics 2011-03-10 A. T. Araudo , G. E. Romero , V. Bosch-Ramon , J. M. Paredes

We show that interactions of fast particles with the boundary shell of the local hot bubble could make an important contribution to the 0.5-1 keV diffuse X-ray background observed with ROSAT. The bulk of these nonthermal X-rays are due to…

Astrophysics · Physics 2009-10-30 V. Tatischeff , R. Ramaty

I give a brief review of high energy gamma-ray signatures of dark matter. The decay of massive $X$-particles and subsequent hadronization have been suggested as the origin of the highest energy cosmic rays. Propagation over cosmological…

Astrophysics · Physics 2009-10-31 R. J. Protheroe

Shocks, turbulence and winds all influence the electron velocity distribution in hot plasmas, exciting lower-energy electrons and generating a high-energy (typically power-law) tail. This effect, typically described as a kappa distribution…

Solar and Stellar Astrophysics · Physics 2020-01-08 Xiaohong Cui , Adam R. Foster , Takayuki Yuasa , Randall K. Smith

Many star-forming galaxies and those hosting active galactic nuclei (AGN) show evidence of massive outflows of material in a variety of phases including ionized, neutral atomic, and molecular. Molecular outflows in particular have been the…

High Energy Astrophysical Phenomena · Physics 2023-02-15 Alex McDaniel , Marco Ajello , Chris Karwin

Gamma ray lines are expected to be emitted as part of the afterglow of supernova explosions, because radioactive decay of freshly synthesised nuclei occurs. Significant radioactive gamma ray line emission is expected from 56Ni and 44Ti…

High Energy Astrophysical Phenomena · Physics 2017-10-25 Roland Diehl

Massive protostars have associated bipolar outflows with velocities of hundreds of km/s. Such outflows produce strong shocks when interact with the ambient medium leading to regions of non-thermal radio emission. Under certain conditions,…

High Energy Astrophysical Phenomena · Physics 2009-08-07 Gustavo E. Romero , Anabella T. Araudo , Valenti Bosch-Ramon , Josep M. Paredes

Recent X-ray observations by the space mission Chandra confirmed the astonishing evidence for a diffuse, hot, thermal plasma at a temperature of 9. $10^7$ K (8 keV) found by previous surveys to extend over a few hundred parsecs in the…

Astrophysics · Physics 2009-11-11 R. Belmont , M. Tagger , M. Muno , M. Morris , S. Cowley

The problem of electromagnetic emission generation in plasma with electron beams is relevant both for practical applications and for interpretation of radio emission processes in astrophysical systems. In this work, we consider the case of…

Plasma Physics · Physics 2023-08-08 Vladimir Annenkov , Evgeniia Volchok , Igor Timofeev

The impact of non-thermal processes on the spectral energy distributions of galaxies can be dramatic, but such processes are often neglected in considerations of their structure and evolution. Particle acceleration associated with high mass…

High Energy Astrophysical Phenomena · Physics 2015-06-04 S. Ohm , J. A. Hinton

We discuss the possibility that the sources for gamma ray bursts are hot neutron stars at cosmological distance scales. The temperature of such stars would be $T \sim 1 \MeV$. Such hot stars can produce an electromagnetic blast wave…

Astrophysics · Physics 2016-08-30 Henning Heiselberg , Sangyong Jeon , Larry McLerran , Hua-Bin Tang

A majority of the $\gamma$-ray emission from star-forming galaxies is generated by the interaction of high-energy cosmic rays with the interstellar gas and radiation fields. Star-forming galaxies are expected to contribute to both the…

Astrophysics of Galaxies · Physics 2020-05-20 M. Ajello , M. Di Mauro , V. S. Paliya , S. Garrappa
‹ Prev 1 2 3 10 Next ›