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Related papers: Supernovae and Positron Annihilation

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We calculate the rate of production of dark photons from electron-positron pair annihilation in hot and dense matter characteristic of supernova progenitors. Given the non-linear dependence of the emission rate on the dark photon mass and…

High Energy Physics - Phenomenology · Physics 2019-07-24 Ermal Rrapaj , Andre Sieverding , Yong-Zhong Qian

Supernova remnants (SNRs) in the Galaxy are an important source of energy injection into the interstellar medium, and also of cosmic rays. Currently there are 294 known SNRs in the Galaxy, and their distribution with Galactocentric radius…

High Energy Astrophysical Phenomena · Physics 2015-10-14 D. A. Green

We selected 27244 nearby, red, giant early-type galaxies (RGEs) from the Sloan Digital Sky Survey (SDSS). In a large fraction (53%) of their spectra the [O III] emission line is detected, with an equivalent width (EW) distribution strongly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Alessandro Capetti , Ranieri D. Baldi

We present a brief summary of asphericity effects in thermonuclear and core collapse supernovae (SN), and how to distinguish the underlying physics by their observable signatures. Electron scattering is the dominant process to produce…

Astrophysics · Physics 2007-05-23 P. Hoeflich , C. Gerardy , R. Quimby

Core collapse of massive stars leads to different fates for various physical factors, which gives different spectra of the emitted neutrinos. We focus on the supernova relic neutrinos (SRNs) as a probe to investigate the stellar collapse…

High Energy Astrophysical Phenomena · Physics 2022-09-27 Yosuke Ashida , Ken'ichiro Nakazato

In the article by Ma~\emph{et al.}~[Phys.~Rev.~A {\bf 94}, 052709 (2016)], $\gamma$-ray spectra for positron annihilation on molecules were calculated in the independent-particle approximation with the positron wavefunction set to unity.…

Atomic Physics · Physics 2017-03-22 D. G. Green , G. F. Gribakin

Novae and supernovae play a key role in many fields of Astrophysics and Cosmology. Despite their importance, an accurate description of which objects explode and why and how they explode is still lacking. One of the main characteristics of…

High Energy Astrophysical Phenomena · Physics 2021-01-11 J. Isern , M. Hernanz , E. Bravo , S. Grebenev , P. Jean , M. Renaud , T. Siegert , J. Vink

We are constructing a model which aims to reproduce observational data of many kinds related to cosmic-ray origin and propagation: direct measurements of nuclei, antiprotons, electrons and positrons, gamma-rays, and synchrotron radiation.…

Astrophysics · Physics 2007-05-23 A. W. Strong , I. V. Moskalenko

Observations of the INTEGRAL satellite revealed the presence of yet unexplained excess in the central region of the Galaxy at the energies around 511 keV. These gamma-rays are produced in the process of positron annihilation, the needed…

High Energy Astrophysical Phenomena · Physics 2016-11-15 Maxim S. Pshirkov

During its first year in orbit the INTEGRAL observatory performed deep exposures of the Galactic Center region and scanning observations of the Galactic plane. We report on the status of our analysis of the positron annihilation radiation…

We present a spectral analysis of the e+e- annihilation emission from the Galactic Centre region based on the first year of measurements made with the spectrometer SPI of the INTEGRAL mission. We have found that the annihilation spectrum…

Astrophysics · Physics 2009-11-13 P. Jean , J. Knodlseder , W. Gillard , N. Guessoum , K. Ferriere , A. Marcowith , V. Lonjou , J. P. Roques

Core-collapse supernovae are among the most fascinating phenomena in astrophysics and provide a formidable challenge for theoretical investigation. They mark the spectacular end of the lives of massive stars and, in an explosive eruption,…

Solar and Stellar Astrophysics · Physics 2012-11-08 H. -Thomas Janka , Florian Hanke , Lorenz Huedepohl , Andreas Marek , Bernhard Mueller , Martin Obergaulinger

The TGRS experiment on board the Wind spacecraft has many advantages as a sky monitor --- broad field of view (~2 pi) centered on the south ecliptic pole), long life (1994-present), and stable low background and continuous coverage due to…

I review our current understanding of positron sources in the Galaxy, on the basis of the reported properties of the observed 511 keV annihilation line. It is argued here that most of the disk positrons propagate away from the disk and the…

Astrophysics · Physics 2009-11-13 N. Prantzos

Peculiar dust extinction laws have been reported for some type Ia supernovae (SNe) with the parameter $R_V$ much lower than the average value for the Milky Way (MW) of 3.1. Using optical photopolarimetry of supernova (SN) host galaxies, a…

Astrophysics of Galaxies · Physics 2025-11-19 João Rino-Silvestre , Santiago González-Gaitán , Ana Mourão , João Duarte , Beatriz Pereira

We calculate the spallative production of light elements associated with the explosion of an isolated supernova in the interstellar medium, using a time-dependent model taking into account the dilution of the ejected enriched material and…

Astrophysics · Physics 2007-05-23 Etienne Parizot , Luke Drury

A very interesting puzzle about the origin of electron and positron cosmic rays is deduced from the latests experimental results. We model the propagation of such cosmic rays in terms of a successfully tested two--zone propagation model.…

Astrophysics of Galaxies · Physics 2014-11-20 Roberto Lineros

We present new nucleosynthesis yields as functions of the stellar mass, metallicity, and explosion energy (corresponding to normal supernovae and Hypernovae). We apply the results to the chemical evolution of the solar neighborhood. Our new…

Astrophysics · Physics 2011-05-05 Ken'ichi Nomoto , Nozomu Tominaga , Hideyuki Umeda , Chiaki Kobayashi , Keiichi Maeda

There are about 70 Galactic supernova remnants (SNRs) that are now confirmed or suggested to be in physical contact with molecular clouds (MCs) with six kinds of evidence of multiwavelength observations. Recent detailed CO-line…

Astrophysics of Galaxies · Physics 2015-06-15 Yang Chen , Bing Jiang , Ping Zhou , Yang Su , Xin Zhou , Hui Li , Xiao Zhang

The electron and positron cosmic rays observations have impulsed a hot debate regarding the origin of such particles. Their propagation in the galactic medium is modeled according to a successfully tested two--zone propagation model. The…

High Energy Astrophysical Phenomena · Physics 2011-02-03 Roberto Lineros
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