Observations of young supernova remnants (SNRs) in X-rays and gamma-rays have provided conclusive evidence for particle acceleration to at least TeV energies. Analysis of high spatial resolution X-ray maps of young SNRs has indicated that the particle acceleration process is accompanied by strong non-adiabatic amplification of magnetic fields. If Fermi acceleration is the mechanism producing the energetic cosmic rays (CRs), the amplified magnetic field must be turbulent and CR-driven instabilities are among the most probable mechanisms for converting the shock ram pressure into the magnetic turbulence. The development and evolution of strong magnetic turbulence in the collisionless plasmas forming SNR shells are complicated phenomena which include the amplification of magnetic modes, anisotropic mode transformations at shocks, as well as the nonlinear physics of turbulent cascades. Polarized X-ray synchrotron radiation from ultra-relativistic electrons accelerated in the SNR shock is produced in a thin layer immediately behind the shock and is not subject to the Faraday depolarization effect. These factors open possibilities to study some properties of magnetic turbulence and here we present polarized X-ray synchrotron maps of SNR shells assuming different models of magnetic turbulence cascades. It is shown that different models of the anisotropic turbulence can be distinguished by measuring the predominant polarization angle direction. We discuss the detection of these features in Tycho's SNR with the coming generation of X-ray polarimeters such as the Imaging X-ray Polarimetry Explorer (IXPE).
Energy released when the core of a high-mass star collapses into a black hole often powers an explosion that creates a supernova remnant. Black holes have limited windows of observability, and consequently are rarely identified in association with supernova remnants. Analysing multi-messenger data, we show that MAXI J1535-571 is the black hole produced in the stellar explosion that gave rise to the supernova remnant G323.7-1.0, making it the first case of an association between a black hole low-mass X-ray binary and a supernova remnant. Given this connection, we can infer from our modelling th…
We report the discovery of a new high mass X-ray binary pulsar, XMMU J050722.1-684758, possibly associated with the supernova remnant MCSNR J0507-6847 in the Large Magellanic Cloud, using XMM-Newton X-ray observations. Pulsations with a periodicity of 570 s are discovered from the Be X-ray binary XMMU J050722.1-684758 confirming its nature as a HMXB pulsar. The HMXB is located near the geometric centre of the supernova remnant MCSNR J0507-6847 (0.9 arcmin from the centre) which supports the XRB-SNR association. The estimated age of the supernova remnant is 43-63 kyr which points to a middle ag…
Particle acceleration to suprathermal energies in strong astrophysical shock waves is a widespread phenomenon, generally explained by diffusive shock acceleration. Such shocks can also amplify upstream magnetic field considerably beyond simple compression. The complex plasma physics processes involved are often parameterized by assuming that shocks put some fraction $ε_e$ of their energy into fast particles, and another fraction $ε_B$ into magnetic field. Modelers of shocks in supernovae, supernova remnants, and gamma-ray bursters, among other locations, often assume typical values for these f…
Understanding the evolution of a supernova remnant shell in time is fundamental. Such understanding is critical to build reliable models of the dynamics of the supernova remnant shell interaction with any pulsar wind nebula it might contain. Here, we perform a large study of the parameter space for the one-dimensional spherically symmetric evolution of a supernova remnant, accompanying it by analytical analysis. Assuming, as is usual, an ejecta density profile with a power-law core and an envelope, and a uniform ambient medium, we provide a set of highly-accurate approximations for the evoluti…
Galactic cosmic rays are believed to be accelerated at supernova remnant shocks. Though very popular and robust, this conjecture still needs a conclusive proof. The strongest support to this idea is probably the fact that supernova remnants are observed in gamma-rays, which are indeed expected as the result of the hadronic interactions between the cosmic rays accelerated at the shock and the ambient gas. However, also leptonic processes can, in most cases, explain the observed gamma-ray emission. This implies that the detections in gamma rays do not necessarily mean that supernova remnants acc…
NGC6946 is a high star formation rate face-on spiral galaxy that has hosted ten supernovae since 1917. Not surprisingly, a large number of supernova remnants and candidates have been identified either as optical nebulae with high [S II]:H$α$ line ratios (147) or as compact non-thermal radio sources (35). However, there are only seven overlaps between these two samples. Here, we apply [Fe II] 1.644 $μ$m emission as a new diagnostic to search for supernova remnants in an attempt to resolve this discrepancy. [Fe II] is expected to be relatively strong in the radiative shocks of supernova remnants…
Probing X-ray Absorption and Optical Extinction in the Interstellar Medium Using Chandra Observations of Supernova Remnants
我们提出了一个全面的研究星际X射线消光使用广泛的钱德拉超新星遗迹档案，并使用我们的结果来完善氢柱密度和光学消光之间的经验关系。在我们的分析中，我们利用大的，统一的数据样本，以评估各种系统的不确定性测量的星际X射线吸收。具体来说，我们解决系统的不确定性，源于（一）用于拟合超新星遗迹光谱的发射模型，（二）在个别遗迹的空间变化，（三）的物理条件的遗迹，如成分，温度和非平衡区，和（四）用于X射线的吸收模型在星际介质。使用贝叶斯框架来量化这些系统的不确定性，并将由此产生的氢柱密度测量结果与相同残留物的光学消光测量结果相结合，我们发现经验关系NH =（2.87+/-0.12）x 10^21 AV cm^（-2），这明显高于以前的测量结果。
