Related papers: How do supernova remnants cool? -- I. Morphology, …
Recent observations have shown several supernova remnants (SNRs) have overionized plasmas, those where ions are stripped of more electrons than they would be if in equilibrium with the electron temperature. Rapid electron cooling is…
We performed deep optical observations of the area of the new supernova remnant G 69.4+1.2 in the emission lines of [O III], Halpha+[N II] and [S II]. The low ionization images reveal diffuse and filamentary emission in the central and…
This paper describes the X-ray emission from supernova remnants evolving in warm, low density, nonthermal pressure dominated regions. Non-equilibrium ionization hydrocode simulations are used to predict the high resolution spectra, ROSAT…
Supernovae (SN) and supernova remnants (SNR) have key roles in galaxies, but their physical descriptions is still incomplete. Thus, it is of interest to study neutrino radiation to understand SN and SNR better. We will discuss: (1) The ~10…
Cooling of neutron stars (NSs) with the cores composed of neutrons, protons, and electrons is simulated assuming $^1$S$_0$ pairing of neutrons in the NS crust, and also $^1$S$_0$ pairing of protons and weak $^3$P$_2$ pairing of neutrons in…
Recent progress in numerical simulations of thermonuclear supernova explosions brings up a unique opportunity in studying the progenitors of Type Ia supernovae. Coupling state-of-the-art explosion models with detailed hydrodynamical…
We have undertaken a study of radio and infrared molecular-line emission towards several SNRs in order to investigate molecular signatures of SNR shocks, and to test models for OH maser production in SNRs. Here we present results on…
Shock interaction in classical novae occurs when a fast outflow from the white dwarf > 1000 km s/s collides with a slower, cooler shell of gas released earlier in the outburst. The shocks radiate across the electromagnetic spectrum, from…
We present the first optical study of the supernova remnant (SNR) G7.7-3.7, with the aim of determining its evolutionary phase since it has been suggested to be the remnant of SN 386 AD. We obtained narrow-band images in the filters…
We present a study of cooling in radiative shocks simulated with smoothed particle hydrodynamics (SPH) and adaptive mesh refinement codes. We obtain a similarity solution for a shock-tube problem in the presence of radiative cooling, and…
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…
The very-high-energy (VHE; E > 100 GeV) gamma-ray emission observed from a number of Supernova remnants (SNRs) indicates particle acceleration to high energies at the shock of the remnants and a potentially significant contribution to…
Evidence for shocks in nova outflows include (1) multiple velocity components in the optical spectra; (2) keV X-ray emission weeks to months after the outburst; (3) early radio flare on timescales of months, in excess of that predicted from…
Type Ia supernovae (SNe Ia) provide unique and important feedback in quiescent galaxies, but their impact has been underappreciated. In this paper, we analyze a series of high-resolution simulations to examine the energetics and turbulence…
We report observations with the MIPS instrument aboard the {\it Spitzer Space Telescope} (SST) of four supernova remnants (SNRs) believed to be the result of core-collapse SNe: N132D (0525-69.6), N49B (0525-66.0), N23 (0506-68.0), and…
We study cosmic-ray acceleration in a supernova remnant (SNR) and the escape from it. We model nonthermal particle and photon spectra for the hidden SNR in the open cluster Westerlund 2, and the old-age mixed-morphology SNR W 28. We assume…
During the first few hundred days after the explosion, core-collapse supernovae (SNe) emit down-scattered X-rays and gamma-rays originating from radioactive line emissions, primarily from the $^{56}$Ni $\rightarrow$ $^{56}$Co $\rightarrow$…
Excess reddened optical emission has been measured in the power-law decay afterglow light curves of several GRBs some tens of days after the GRB events. This emission is claimed to be a signature of a supernova (SN) taking place at the same…
The hydrodynamic state of the interstellar medium (ISM) heated and randomly stirred by supernovae (SNe) is investigated. We use a three-dimensional non-ideal hydrodynamic ISM model in a domain extending 0.5 x 0.5 kpc horizontally and 2 kpc…
Shocks are often invoked as heating mechanisms in astrophysical systems, with both adiabatic compression and dissipative heating that leading to temperature increases. Whilst shocks are reasonably well understood for ideal…