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Related papers: A grey gamma-ray transfer procedure for supernovae

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Gamma camera imaging is an important technique in nuclear medicine. It is capable of diagnostic imaging of metabolically active areas and organ function, and it can be used to evaluate blood flow in the heart muscle, measure bone growth,…

Medical Physics · Physics 2022-01-12 Mary Lowe , Alex Spiro , Peter Kutt

An extraordinarily efficient mechanism, operating at high laser intensities and powers, is identified for spectral transferring huge laser energies to shorter ultraviolet and x-ray wavelengths. With megajoule laser energies currently…

Plasma Physics · Physics 2020-03-04 V. M. Malkin , N. J. Fisch

Recent EGRET observations of the diffuse Galactic gamma-ray emission reveal a spectrum which is incompatible with the assumption that the cosmic ray spectra measured locally hold throughout the Galaxy: the spectrum above 1 GeV, where the…

Astrophysics · Physics 2009-11-07 I. Büsching , M. Pohl , R. Schlickeiser

The collective nature of light interactions with atomic and nuclear ensembles yields the fascinating phenomena of superradiance and radiation trapping. We study the interaction of gamma rays with a coherently vibrating periodic array of…

Quantum Physics · Physics 2013-10-02 Xiwen Zhang , Anatoly A. Svidzinsky

The energetics of optical and radio afterglows following BeppoSAX and BATSE gamma-ray bursts (GRBs) suggests that gamma-ray emission is not narrowly collimated, but a moderate beaming is possible, so the total energy of a GRB may be in the…

Astrophysics · Physics 2009-10-30 Bohdan Paczyński

Gravitational wave observations need accompanying electromagnetic signals to accurately determine the sky positions of the sources. The ejecta of neutron star mergers are expected to produce such electromagnetic transients, called…

High Energy Astrophysical Phenomena · Physics 2017-02-13 Christopher J. Fontes , Chris L. Fryer , Aimee L. Hungerford , Ryan T. Wollaeger , Stephan Rosswog , Edo Berger

High energy electrons and positrons from decaying dark matter can produce a significant flux of gamma rays by inverse Compton off low energy photons in the interstellar radiation field. This possibility is inevitably related with the dark…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Le Zhang , Christoph Weniger , Luca Maccione , Javier Redondo , Guenter Sigl

Material ejected during (or immediately following) the merger of two neutron stars may assemble into heavy elements by the r-process. The subsequent radioactive decay of the nuclei can power electromagnetic emission similar to, but…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Daniel Kasen , N. R. Badnell , Jennifer Barnes

In this paper we discuss the possibility of the excitation of nuclear electromagnetic transitions by the absorption of X-ray quanta produced in appropriate inner-shell atomic transitions, and the relevance of this process for the…

Nuclear Experiment · Physics 2007-05-23 Silviu Olariu

We extend earlier calculations of the attenuation suffered by gamma rays during their propagation from extragalactic sources, obtaining new extinction curves for gamma rays down to 10 GeV in energy, from sources up to a redshift of z=3.

Astrophysics · Physics 2009-10-30 M. H. Salamon , F. W. Stecker

A light pseudoscalar coupled to two photons would be copiously emitted by the core of a supernova. Part of this flux would be converted to $\gamma-$rays by the galactic magnetic field. Measurements on the SN1987A $\gamma-$ray flux by the…

Astrophysics · Physics 2009-10-28 J. A. Grifols , E. Masso , R. Toldra

Deconvolution algorithms have been used successfully for optimization/restoration/deblurring of astronomical images in a variety of wavelengths, especially in the optical band (e.g., for HST). We present here an iterative Richardson-Lucy…

Astrophysics · Physics 2007-11-15 G. Maurin , A. Djannati-Atai , P. Espigat

The mergers of compact binaries with at least one neutron star component are the potential leading sites of the production and ejection of $r$-process elements. Discoveries of galactic binary pulsars, short gamma-ray bursts, and…

We introduce and test a new and highly efficient method for treating the thermal and radiative effects influencing the energy equation in SPH simulations of star formation. The method uses the density, temperature and gravitational…

Astrophysics · Physics 2009-11-13 D. Stamatellos , A. P. Whitworth , T. Bisbas , S. Goodwin

We show that mid infrared transmission spectroscopy of a quantum cascade laser provides clear cut information on changes in charge location at different bias. Theoretical simulations of the evolution of the gain/absorption spectrum for the…

Mesoscale and Nanoscale Physics · Physics 2007-12-05 R. Nelander , A. Wacker , M. F. Pereira , D. G. Revin , M. R. Soulby , L. R. Wilson , J. W. Cockburn , A. B. Krysa , J. S. Roberts , R. J. Airey

Gamma-ray binaries are suitable sources to study high-energy processes in jets and outflows in general. In the last years, there has been a lot of activity in the field of gamma-ray binaries to identify the different factors that shape…

High Energy Astrophysical Phenomena · Physics 2010-08-04 V. Bosch-Ramon

We present calculations of the radio emission from supernovae based on high-resolution simulations of the hydrodynamics and radiation transfer, using simple energy density relations which link the properties of the radiating electrons and…

Astrophysics · Physics 2009-11-07 Amy J. Mioduszewski , Vikram V. Dwarkadas , Lewis Ball

High-energy photons emitted from gamma-ray bursts (GRBs) are subject to pair-production interactions with lower energy photons, leading to an effective optical depth. In this Letter, we estimate the opacity resulting from photon fields…

High Energy Astrophysical Phenomena · Physics 2010-11-02 Rudy C. Gilmore , Enrico Ramirez-Ruiz

Context: Several binary systems hosting massive stars present gamma-ray emission. In most of these systems, despite detailed observational information being available, the nature and the structure of the emitter are still poorly known.…

High Energy Astrophysical Phenomena · Physics 2015-03-11 Santiago del Palacio , Valentí Bosch-Ramon , Gustavo E. Romero

The transmission matrix (TM) is a representation to describe the light scattering process through a scattering medium. The degree of control elements in TM is correlated with the capacity of evaluating enormous equations with tremendous…

Optics · Physics 2020-11-25 Shu Guo , Hao Zhang , Wenxue Li , Lin Pang