Related papers: Reverse and Forward Shock X-ray Emission in an Evo…
Recent observations by the Large Area Telescope (LAT) onboard the Fermi satellite have revealed bright gamma-ray emission from middle-aged supernova remnants (SNRs) inside our Galaxy. These remnants, which also possess bright non-thermal…
Supernova remnants (SNRs) are widely believed to be the principal source of galactic cosmic rays. Such energetic particles can produce gamma-rays and lower energy photons via interactions with the ambient plasma. In this paper, we present…
A number of nearby Northern Hemisphere shell-type Supernova Remnants (SNRs) has been observed in TeV gamma rays, but none of them could be detected so far. This failure calls for a critical reevaluation of the theoretical arguments for…
The end of supernova remnant (SNR) evolution is characterized by a so-called "radiative" stage, in which efficient cooling of the hot bubble inside the forward shock slows expansion, leading to eventual shock breakup. Understanding SNR…
Supernovae (SNe) with strong interactions with circumstellar material (CSM) are promising candidate sources of high-energy neutrinos and gamma rays, and have been suggested as an important contributor to Galactic cosmic rays beyond 1 PeV.…
Cosmic-ray production in young supernova remnant (SNR) shocks is expected to be efficient and strongly nonlinear. In nonlinear, diffusive shock acceleration, compression ratios will be higher and the shocked temperature lower than…
We present results of semi-analytic calculations which show clear evidence for changes in the non-equilibrium ionization behind a supernova remnant forward shock undergoing efficient diffusive shock acceleration (DSA). The efficient…
We present a grid of nonequilibrium ionization models for the X-ray spectra from supernova remnants undergoing efficient diffusive shock acceleration. The calculation follows the hydrodynamics of the blast wave as well as the time-dependent…
Supernovae of type Ia (SNe Ia) are very important for cosmography. To exclude systematic effects in linking the observed light of distant SNe Ia to the parameters of cosmological models, one has to understand the nature of supernova…
Recent nonthermal X-ray and gamma-ray observations, attributed to electron emission processes, for the first time give an experimental confirmation that electrons are accelerated on SNR shocks up to the energy 10^{14} eV. We have no direct…
According to the most popular model for the origin of cosmic rays (CRs), supernova remnants (SNRs) are the site where CRs are accelerated. Observations across the electromagnetic spectrum support this picture through the detection of…
Supernova remnants (SNRs) are a complex class of sources, and their heterogeneous nature has hindered the characterization of their general observational properties. To overcome this challenge, we use statistical tools to analyze the…
Diffusive shock acceleration in the environs of a remnant's expanding shell is a popular candidate for the origin of SNR gamma-rays. In this paper, results from our study of non-linear effects in shock acceleration theory and their impact…
Supernova remnants (SNRs) offer the means to study SN explosions, dynamics, and shocks at sub-parsec scales. X-ray observations probe the hot metals synthesized in the explosion and the TeV electrons accelerated by the shocks, and thus they…
Two main physical mechanisms are used to explain supernova explosions: thermonuclear explosion of a white dwarf(Type Ia) and core collapse of a massive star (Type II and Type Ib/Ic). Type Ia supernovae serve as distance indicators that led…
We study cosmic-ray acceleration in young Type Ia Supernova Remnants (SNRs) by means of test-particle diffusive shock acceleration theory and 1-D hydrodynamical simulations of their evolution. In addition to acceleration at the forward…
Context: Multiwavelength observations of supernova remnants can be explained within the framework of the diffusive shock acceleration theory, which allows effective conversion of the explosion energy into cosmic rays. Although the models of…
Recent gamma-ray observations show that middle aged supernova remnants (SNRs) interacting with molecular clouds (MCs) can be sources of both GeV and TeV emission. Based on the MC association, two scenarios have been proposed to explain the…
While supernova remnants (SNRs) have long been considered prime candidates as sources of cosmic rays, it is only recently that X-ray observations have identified several shell-type SNRs dominated by nonthermal emission, thus revealing…
While various methods have been proposed to disentangle the progenitor system for Type Ia supernovae, their origin is still unclear. Circumstellar environment is a key to distinguishing between the double-degenerate (DD) and…