Related papers: Probing clumpy stellar winds with a neutron-star
High-resolution X-ray spectra of O-type stars revealed less wind absorption than expected from smooth winds with conventional mass-loss rates. Various solutions have been proposed, including porous winds, optically thick clumps or an…
We report results from an investigation at hard X-rays (above 18 keV) and soft X-rays (below 10 keV) of a sample of X-ray transients located on the Galactic plane and detected with the bursticity method, as reported in the latest 1,000…
In the past fifteen years a new generation of X-ray satellites led to the discovery of a subclass of high-mass X-ray binaries (HMXBs) with supergiant companions and a peculiar transient behaviour: supergiant fast X-ray transients (SFXTs).…
The study of soft X-ray emission of 38 X-ray selected galaxy clusters observed by ROSAT PSPC indicates that the soft excess phenomenon may be a common occurrence in galaxy clusters. Excess soft X-ray radiation, above the contribution from…
In wind-powered X-ray binaries, the radiatively driven stellar wind from the primary may be inhibited by the X-ray irradiation. This creates the feedback that limits the X-ray luminosity of the compact secondary. Wind inhibition might be…
We use 3D hydrodynamical models to investigate the effects of massive star feedback from winds and supernovae on inhomogeneous molecular material left over from the formation of a massive stellar cluster. We simulate the interaction of the…
A significant fraction of high-mass X-ray binaries are supergiant fast X-ray transients (SFXTs). The prime model for the physics governing their X-ray behaviour suggests that the winds of donor OB supergiants are magnetized. To investigate…
Binary systems containing a massive star and a non-accreting pulsar present strong interaction between the stellar and the pulsar winds. The properties of this interaction, which largely determine the non-thermal radiation in these systems,…
Binaries hosting a massive star and a non-accreting pulsar are powerful non-thermal emitters due to the interaction of the pulsar and the stellar wind. The winds of massive stars are thought to be inhomogeneous, which could have an impact…
Stellar winds contain enough energy to easily disrupt the parent cloud surrounding a nascent star cluster, and for this reason have been considered candidates for regulating star formation. However, direct observations suggest most wind…
A fraction of high-mass X-ray binaries are supergiant fast X-ray transients. These systems have on average low X-ray luminosities, but display short flares during which their X-ray luminosity rises by a few orders of magnitude. The leading…
The INTEGRAL satellite, observing the sky at high energy, has quadrupled the number of supergiant X-ray Binaries known in the Galaxy and has revealed new populations of previously hidden High Mass X-ray Binaries. These observations raise…
Towards the end of their evolution hot massive stars develop strong stellar winds and appear as emission line stars, such as WR stars or LBVs. The quantitative description of the mass loss in these important pre-SN phases is hampered by…
The relationship between star formation and infrared emission in galaxies will be investigated. If galaxies were simple objects and young stars were completely covered with dust, then all the absorbed light of the young stars would be…
We report on a broad-band X-ray study (0.5-60 keV) of the poorly known candidate Supergiant Fast X-ray Transient (SFXT) IGR J18462-0223, and on optical and near-infrared (NIR) followup observations of field objects. The out-of-outburst…
B supergiants (BSGs) are evolved stars with effective temperatures between 10 to 30 kK and are important to understand massive star evolution. Located on the edge of the line-driven wind regime, the study of their atmospheres is helpful to…
Many observed massive star-forming z\approx2 galaxies are large disks that exhibit irregular morphologies, with \sim1kpc, \sim10^(8-10)Msun clumps. We present the largest sample to date of high-resolution cosmological SPH simulations that…
We present results of the study of persistent high mass X-ray binaries (HMXBs) in the Milky Way, obtained from the deep INTEGRAL Galactic plane survey. This survey provides us a new insight into the population of high mass X-ray binaries…
Galactic superwinds may be driven by very hot outflows generated by overlapping supernovae within the host galaxy. We use the Chevalier & Clegg (CC85) wind model and the observed correlation between X-ray luminosities of galaxies and their…
In this review I briefly describe the nature of the three kinds of High-Mass X-ray Binaries (HMXBs), accreting through: (i) Be circumstellar disc, (ii) supergiant stellar wind, and (iii) Roche lobe filling supergiants. A previously unknown…