Related papers: Highly structured wind in Vela X-1
X-ray binary accretion disk winds can carry away a significant fraction of the matter transferred from the companion and hence strongly affect the accretion flow and the long-term evolution of the binary. However, accurate mass outflow rate…
In this paper, we present a full spatially resolved polarization map for the Vela Pulsar Wind Nebula (PWN) observed by IXPE. By employing effective background discrimination techniques, our results show a remarkably high degree of local…
Vela X is a nearby pulsar wind nebula (PWN) powered by a $\sim 10^4$ year old pulsar. Modeling of the spectral energy distribution of the Vela X PWN has shown that accelerated electrons have largely escaped from the confinement, which is…
We present Rossi X-ray Timing Explorer observations of the X-ray pulsar SMC X-1. The source is highly variable on short time scales (< 1 h), exhibiting apparent X-ray flares occupying a significant fraction (~3 %) of the total observing…
We present results from Hubble Space Telescope UV spectroscopy of the massive X-ray binary system, HD226868 = Cyg X-1. The spectra were obtained at both orbital conjunction phases in two separate runs in 2002 and 2003 when the system was in…
A plausible model for the Crab Nebula is one in which a particle dominated, highly relativistic wind from the pulsar passes through a shock front in which the particles attain a power law energy distribution. The electrons and positrons…
We report simultaneous observations of the nearby flare star Proxima Centauri with VLT/UVES and XMM-Newton over three nights in March 2009. Our optical and X-ray observations cover the star's quiescent state, as well as its flaring activity…
We report on the full analysis of a Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) monitoring of the {\gamma}-ray binary system LS I +61 303. The data set covers 42 contiguous cycles of the system orbital motion.…
We present the results of a campaign to observe flares on the M dwarf flare star EV Lacertae over the course of two days in 2001 September, utilizing a combination of radio continuum, optical photometric and spectroscopic, ultraviolet…
Vela X is a pulsar wind nebula in which two relativistic particle populations with distinct spatial and spectral distributions dominate the emission at different wavelengths. An extended $2^\circ \times 3^\circ$ nebula is seen in radio and…
We present results from the first radio observations of a complete orbit (~ 17 days) of the neutron star X-ray binary Circinus X-1 using the Australia Telescope Compact Array Broadband Backend, taken while the system was in an historically…
Strong outflows from active galactic nuclei are frequently observed in objects with lower coronal X-ray luminosity. This intrinsic X-ray weakness is considered a requirement for the formation of radiatively driven winds. To obtain an…
Hercules X-1 is a nearly edge-on X-ray binary with a warped, precessing accretion disk, which manifests through a 35-day cycle of alternating High and Low flux states. This disk precession introduces a changing line of sight towards the…
Aims: We have developed a new code for the three-dimensional time-dependent raditation hydrodynamic simulation of the stellar wind in interacting binaries to improve models of accretion in high-mass X-ray binaries and to quantitatively…
In high-mass X-ray binaries (HMXBs), the compact object accretes the strong stellar wind of an O-B supergiant companion star. X-ray flux variations alter the stellar wind's ionization state and optical line profiles, which are key in the…
After 25 years of quiescence, the microquasar V404 Cyg entered a new period of activity in June 2015. This X-ray source is known to undergo extremely bright and variable outbursts seen at all wavelengths. It is therefore an object of prime…
Results of GRANAT/ART-P observations of three X-ray pulsars in non-pulsing states are presented: 1) a statistically significant non-pulsing flux with a simple power-law spectrum was detected during the ``off''- state of Her X-1; 2) a…
Chandra observations of the Vela pulsar-wind nebula (PWN) have revealed a jet in the direction of the pulsar's proper motion, and a counter-jet in the opposite direction, embedded in diffuse nebular emission. The jet consists of a bright,…
Pulsar wind nebulae (PWNe) are among the most extreme particle accelerators in galaxies, are recognized as multi-TeV electron/positron sources, and are one of the dominant classes of Galactic gamma-ray sources. Vela X is a nearby PWN at 290…
The stellar-wind structure in high-mass X-ray binaries (HMXBs) is investigated through modelling of their ultraviolet (UV) resonance lines. For the OB supergiants in two systems, Vela X-1 and 4U1700-37, high-resolution UV spectra are…