Related papers: Shell-Shocked: The Interstellar Medium Near Cygnus…
The X-ray binary Cygnus X-3 is a highly variable X-ray source that displays a wide range of observed spectral states. One of the main states is significantly harder than the others, peaking at ~ 20 keV, with only a weak low-energy…
We examine the case where a circumstellar medium around a supernova is sufficiently opaque that a radiation dominated shock propagates in the circumstellar region. The initial propagation of the shock front into the circumstellar region can…
High resolution HI observations of nearby dwarf galaxies (most of which are situated in the M 81 group at a distance of about 3.2 Mpc) reveal that their neutral interstellar medium (ISM) is dominated by hole-like features most of which are…
The evolution of massive stars is influenced by the mass lost to stellar winds over their lifetimes. These winds limit the masses of the stellar remnants (such as black holes) that the stars ultimately produce. We use radio astrometry to…
We examine flash spectroscopy of a circumstellar medium (CSM) ionized by the hard radiation pulse produced by the emerging shock of a supernova (SN). We first find that the rise and fall times of the Halpha emission constrains the location…
Observations indicate that optically thick circum-stellar medium (CSM) at radii of $10^{14}-10^{15}~$cm around Type II core-collapse supernovae (SN) progenitors is common (and may be present in other types of massive star explosions). The…
Using three-dimensional magnetohydrodynamics simulations, we investigate general properties of a blast wave shock interacting with interstellar clouds. The shock-cloud interaction generates a turbulent shell through the vorticity…
The interstellar medium (ISM) is constantly evolving due to unremitting injection of energy in various forms. Energetic radiation transfers energy to the ISM: from the UV photons, emitted by the massive stars, to X- and $\gamma$-ray ones.…
Interstellar dust permeates our Galaxy and plays an important role in many physical processes in the diffuse and dense regions of the interstellar medium. High-resolution X-ray spectroscopy, coupled with modelling based on laboratory dust…
High-resolution IRAS maps are used to search for the presence of stellar-wind bow-shocks around high-mass X-ray binaries (HMXBs). Their high space velocities, recently confirmed with Hipparcos observations, combined with their strong…
(Shortened) Ultraviolet observations of the black hole X-ray binary Cygnus X-1 were obtained using the STIS on HSTubble. We detect P Cygni line features show strong, broad absorption components when the X-ray source is behind the companion…
A pair of non-thermal radio bubbles recently discovered in the inner few hundred parsecs of the Galactic center bears a close spatial association with elongated, thermal X-ray features called the X-ray chimneys. While their morphology,…
We present four epochs of high-resolution infrared spectroscopy of the peculiar X-ray binary Cygnus X-3. The observations cover quiescent, small flaring and outburst states of the system as defined by radio and X-ray monitoring. The…
Gamma-ray observations of microquasars at high and very-high energies can provide valuable information of the acceleration processes inside the jets, the jet-environment interaction and the disk-jet coupling. Two high-mass microquasars have…
Spatially resolved images of the galactic supernova remnant G78.2+2.1 (gamma-Cygni) in hard X-ray energy bands from 25 keV to 120 keV are obtained with the IBIS-ISGRI imager aboard the International Gamma-Ray Astrophysics Laboratory…
Observations have suggested substantial departures from pressure equilibrium in the interstellar medium (ISM) in the plane of the Galaxy, even on scales under 50 pc. Nevertheless, multi-phase models of the ISM assume at least locally…
Optical and radio observations of shock-ionised bubble nebulae surrounding ultraluminous X-ray sources (ULXs) suggest that they are powered by jets or super-critical outflows presumably launched from the ULX accretion disc. Recent…
Observations have suggested substantial departures from pressure equilibrium in the interstellar medium (ISM) in the plane of the Galaxy, even on scales under 50 pc. Nevertheless, multi-phase models of the ISM assume at least locally…
Orbital-phased-resolved infrared spectra of Cygnus X-3 in outburst and quiescence, including tomographic analysis, are presented. We confirm the phasing of broad HeII and NV lines in quiescence, such that maximum blue shift corresponds to…
We describe the propagation of supernova shocks within the surrounding medium, which may be due to mass-loss from the progenitor star. The structure and density profile of the ejected material and surrounding medium are considered. Shock…