Related papers: Cassiopeia A and its Clumpy Presupernova Wind
We study the evolution of supernova remnants in the circumstellar medium formed by mass loss from the progenitor star. The properties of this interaction are investigated, and the specific case of a 35 $\msun$ star is studied in detail. The…
Cassiopeia A (Cas A) is the youngest known core-collapse supernova remnant (SNR) in the Galaxy and is perhaps the best-studied SNR in X-rays. Cas A has a line-rich spectrum dominated by thermal emission and given its high flux, it is an…
We report the detection of the slow moving wind into which the compact supernova remnant SN 1997ab is expanding. Echelle spectroscopy provides clear evidence for a well resolved narrow (Full Width at Zero Intensity, FWZI ~ 180 km/s) P-Cygni…
We present an analysis of three Chandra High Energy Transmission Gratings observations of the black hole binary Cyg X-1/HDE 226868 at different orbital phases. The stellar wind that is powering the accretion in this system is characterized…
A variety of supernova events, including Type IIn supernovae and ultraluminous supernovae, appear to have lost up to solar masses of their envelopes in 10's to 100's of years leading up to the explosion. In order to explain the close timing…
Fast line-driven stellar winds play an important role in the evolution of planetary nebulae. We provide global hot star wind models of central stars of planetary nebulae. The models predict wind structure including the mass-loss rates,…
We present high-resolution X-ray spectra from the young supernova remnant Cas A using a 70-ks observation taken by the Chandra High Energy Transmission Grating Spectrometer (HETGS). Line emission, dominated by Si and S ions, is used for…
Circumstellar interaction has been observed around all types of massive star supernovae, especially at radio and X-ray wavelengths. The interaction shells in Type Ib/c supernovae appear to be moving rapidly, although SN 1998bw remains the…
We show a scenario for the cooling of compact stars considering the central source of Cassiopeia A (Cas A). The Cas A observation shows that the central source is a compact star with high effective temperature, and it is consistent with the…
Evidence indicates that supermassive black holes exist at the centers of most galaxies. Their mass correlates with the galactic bulge mass, suggesting a co-evolution with their host galaxies, most likely through powerful winds. X-ray…
High-velocity features (HVF), especially of Ca II, are frequently seen in Type Ia supernova observed prior to B-band maximum (Bmax). These HVF evolve in velocity from more than 25,000 km/s, in the days after first light, to about 18,000…
Evidence of high-velocity features such as those seen in the near-maximum spectra of some Type Ia Supernovae (eg SN 2000cx) has been searched for in the available SNIa spectra observed earlier than one week before B maximum. Recent…
Massive stars lose a significant fraction of mass during their evolution. However, the corresponding mass-loss rates are rather uncertain. To improve this, we calculated global line-driven wind models for Galactic B supergiants. Our models…
Mass loss governs the evolution of massive stars and shapes the stellar surroundings. To quantify the impact of the stellar winds we need to know the exact mass-loss rates; however, empirical constraints on the rates are hampered by limited…
Only a handful of supernovae (SNe) have been studied in multi-wavelength from radio to X-rays, starting a few days after explosion. The early detection and classification of the nearby type IIb SN2011dh/PTF11eon in M51 provides a unique…
Context. Fast-moving knots (FMK) in the Galactic supernova remnant Cassiopeia A consist mainly of metals and allow to study element production in supernovae and shock physics in great detail. Aims. We work out theoretically and suggest to…
Supernova remnants (SNRs) offer the means to study supernovae (SNe) long after the original explosion and can provide a unique insight into the mechanism that governs these energetic events. In this work, we examine the morphologies of…
The young SNR Cassiopeia A was imaged with WFPC-2 through four filters selected to capture the complete velocity range of the remnant's main shell in several important emission lines. Primary lines detected were [O III] 4959,5007, [N II]…
We show that the diversity in the density slope of the dense wind due to non-steady mass loss can be one way to explain the spectral diversity of Type II luminous supernovae (LSNe). The interaction of SN ejecta and wind surrounding it is…
(Abridged) Mass-loss from massive stars leads to the formation of circumstellar wind-blown bubbles surrounding the star, bordered by a dense shell. When the star ends its life in a supernova (SN) explosion, the resulting shock wave will…