Related papers: Nonthermal Bremsstrahlung vs. Synchrotron Radiatio…
We report the discovery of spatially-extended, non-thermal-like emission components in Chandra X-ray spectra for five of a sample of seven massive, merging galaxy clusters with powerful radio halos. The emission components can be fitted by…
We study the time-resolved spectra of eight GRBs observed by Fermi GBM in its first five years of mission, with 1 keV - 1 MeV fluence $f>1.0\times10^{-4}$ erg cm$^{-2}$ and signal-to-noise level $\text{S/N}\geq10.0$ above 900 keV. We aim to…
(abridged)Prompt GRB emission is often interpreted as synchrotron radiation from high-energy electrons accelerated in internal shocks. Fast synchrotron cooling predicts that the photon index below the spectral peak is alpha=-3/2. This…
In this Letter we use the unprecedented spatial resolution of the Chandra X-ray Observatory to carry out, for the first time, a measurement of the post-shock electron temperature and proper motion of a young SNR, specifically to address…
Thin non-thermal X-ray filaments are often seen in young supernova remnants. We used data from the 1 Ms Chandra observation of Cassiopeia A to study spectral properties of some of the filaments in this remnant. For all the cases that we…
In the previous numerical study, we find the blob formation and ejection in the presence of magnetic reconnection in the environment of the hot flow of the accretion disk. Based on those encouraging results, in the present work, we…
The estimated brightness of the Cygnus loop supernova remnant (SNR) at 2720, 1420, 820, 408 and 34.5 MHz are presented. The observations of the continuum radio emission are used to calculate the mean brightness temperatures and surface…
Nonreciprocal thermal emitters that break the conventional Kirchhoff's law allow independent control of emissivity and absorptivity and promise exciting new functionalities in controlling heat flow for thermal and energy applications. In…
Recent measurements of the positron energy spectrum obtained from inverse beta decay interactions of reactor electron antineutrinos show an excess in the 4 to 6 MeV region relative to current predictions. First-principle calculations of…
Resolved maps of the thermal and nonthermal radio continuum (RC) emission of distant galaxies are a powerful tool for understanding the role of the interstellar medium (ISM) in the evolution of galaxies. We simulate the RC surface…
Using ASCA, spatially integrated X-ray spectra of the central regions of M31 were studied. Data were accumulated over three different circular regions, with the radii of 3', 6' and 12', all centered on the nucleus. The spectra are…
We have performed the first detailed spatially resolved spectroscopy of Cas A in the 1.6-10 keV energy range, using data taken with the MECS spectrometer on board the BeppoSAX Observatory. We performed a spatial deconvolution of the data…
Bremsstrahlung from relativistic electrons is considered under conditions when some transverse direction of momentum transfer is statistically preferred. It is shown that in the dipole approximation all the medium anisotropy effects can be…
Based on the data from the observation of the SNR G327.1-1.1 by ASCA and ROSAT, we find that G327.1-1.1 is a composite remnant with both a nonthermal emission component and a diffuse thermal emission component. The nonthermal component is…
We investigate the radiation from a charged particle rotating around a dielectric cylinder with a negative real part of dielectric permittivity. For the general case of frequency dispersion in dielectric permittivity, expressions are…
We study the impact of the nucleon-$\alpha$ P-wave resonances on neutrino-pair bremsstrahlung. Because of the non-central spin-orbit interaction, these resonances lead to an enhanced contribution to the nucleon spin structure factor for…
We make the first observation-based calculation of the energy that goes into cosmic-ray protons versus cosmic ray electrons in shock acceleration during structure formation. We find a ratio of energy in cosmic ray protons to energy in…
We present the analysis of archival data from the Advanced Satellite for Cosmology and Astrophysics} (ASCA) of the supernova remnant (SNR) G39.2-0.3. G39.2-0.3 has been sometimes characterized as a shell-like remnant in the literature but…
Synchrotron X-ray emission in young supernova remnants (SNRs) is a powerful diagnostic tool to study the population of high energy electrons accelerated at the shock front and the acceleration process. We performed a spatially resolved…
We show that the spectral and radial distribution of the nonthermal emission of massive, M>10^{14.5}M_sun, galaxy clusters (GCs) may be approximately described by simple analytic expressions, which depend on the GC thermal X-ray properties…