相关论文: Temporal and Spatial Variation of Synchrotron X-ra…
The quest for the origin of cosmic ray (CRs) is a fundamental issue in astrophysics. Shocks of supernova remnants (SNRs) have been considered as the dominant contributors to Galactic CRs below the spectral knee near $\sim 3$…
The detection of very-high-energy gamma rays from supernova remnant shells testifies of the acceleration of particles at strong shocks. Many aspects of the particle acceleration remain however unclear. The study of individual objects is…
We present results from a study of optically emitting Supernova Remnants (SNRs) in six nearby galaxies (NGC 2403, NGC 3077, NGC 4214, NGC 4395, NGC 4449 and NGC 5204) based on deep narrow band H{\alpha} and [SII] images as well as…
Context. Supernova remnants (SNRs) are thought to be the main source of Galactic cosmic rays (CRs) up to the "knee" in CR spectrum. During the evolution of a SNR, the bulk of the CRs are confined inside the SNR shell. The highest-energy…
Multi-wavelength observations of mature supernova remnants (SNRs), especially with recent advances in gamma-ray astronomy, make it possible to constrain energy distribution of energetic particles within these remnants. In consideration of…
This thesis is devoted to the analysis of X-ray observations of supernova remnants (SNRs), exploiting the diagnostic potential provided by X-ray spectroscopy and complementing it with the synthesis of X-ray observables from…
Particle acceleration physics at supernova remnant (SNR) shocks is one of the most intriguing problems in astrophysics. SNR RCW~86 provides a suitable environment for understanding the particle acceleration physics because one can extract…
We propose that a non-thermal X-ray arc inside the remnant of Tycho's supernova (SN) represents the interaction between the SN ejecta and the companion star's envelope lost in the impact of the explosion. The X-ray emission of the remnant…
Tycho's supernova remnant (SNR) has a periphery which clearly deviates from spherical shape bash on the X-ray and radio observations. The forward shock from the southeast to the north of the remnant has a relatively deformed outline with a…
We present a spatially resolved study of the kinematical properties of known supernova remnants (SNRs) in the nearest galaxies of the SIGNALS survey, namely NGC 6822 (one object) and M33 (163 objects), based on data obtained with the…
Recent Fermi and VERITAS observations of the prototypical Type Ia supernova remnant (SNR) Tycho have discovered gamma-rays with energies E in the range from ~0.4 GeV to 10 TeV. Crucial for the theory of Galactic cosmic-ray origin is whether…
We have observed the Galactic supernova remnant G16.7+0.1 for 13 ks using the EPIC cameras aboard the XMM-Newton X-ray Observatory, producing the first detection of the SNR outside of the radio band. G16.7+0.1 is one of the faintest radio…
Supernova remnants (SNRs) exhibit varying degrees of anisotropy, which have been extensively modeled using numerical methods. We implement a technique to measure anisotropies in SNRs by calculating power spectra from their high-resolution…
We present results of a search for supernova remnants (SNRs) in archival Chandra images of M33. We have identified X-ray SNRs by comparing the list of Chandra, X-ray sources in M33 with tabulations of SNR candidates identified from (1)…
Two ROSAT high resolution images separated by nearly five years have been used to determine the expansion of the X-ray remnant of Tycho's supernova (SN1572). The current expansion rate averaged over the entire remnant is $0.124\pm0.011$ %…
We show that the expansion of ejecta in Tycho's supernova remnant (SNR) is consistent with a spherically symmetric shell, based on Suzaku measurements of the Doppler broadened X-ray emission lines. All the strong K_alpha line emission show…
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…
Recent studies of narrow, X-ray synchrotron radiating filaments surrounding young supernova remnants indicate that magnetic fields strengths are relatively high, B ~ 0.1 mG, or even higher, and that diffusion is close to the Bohm limit. I…
Supernova remnants (SNRs) are powerful particle accelerators. As a supernova (SN) blast wave propagates through the circumstellar medium (CSM), electrons and protons scatter across the shock and gain energy by entrapment in the magnetic…
The idea that the shocks from supernova remnants (SNR) expanding into the interstellar medium (ISM) accelerate CR is still popular one but a number of authors have drawn attention to the fact that the experimental evidence for the presence…