Related papers: SS433: a massive X-ray binary at advanced evolutio…
The X-ray binary SS 433, embedded in the W50 nebula (or supernova remnant W50), shows bipolar jets that are ejected with mildly relativistic velocities, and extend toward the east and west out to scales of tens of parsecs. Previous X-ray…
Chandra has resolved the starburst nuclear region of the face-on grand-design spiral M83. Eighty-one point sources are detected above 3.5 sigma in the ACIS S3 image, and 15 of them are within the inner 16-arcsec region of the galaxy. A…
More than 150 measurements of the HeII 4686A emission line in spectra of SS433 were obtained during 388 nights in 2020-2025 with the Transient Double-beam Spectrograph on the 2.5 m telescope of Caucasian Mountain Observatory of Sternberg…
We report on the results from Suzaku broadband X-ray observations of the galactic binary source LS5039. The Suzaku data, which have continuous coverage of more than one orbital period, show strong modulation of the X-ray emission at the…
X-ray emission is an important tracer of stellar magnetic activity. We carried out a systematic correlation analysis for the X-ray luminosity $\log L_{\rm X}$, bolometric luminosity $\log L_{\rm bol}$, and X-ray activity level…
We propose that the polarization of the emission from the X-ray binary Cygnus X-1, measured using the Imaging X-ray Polarimetry Explorer (IXPE), is imprinted by bulk Comptonization of coronal emission in a mildly relativistic wind or jet…
X-ray emission processes in starburst galaxies (SBGs) are assessed, with the aim of identifying and characterizing the main spectral components. Our survey of spectral properties, complemented with a model for the evolution of galactic…
This paper surveys our current knowledge of the hard X-ray emission properties of old accreting neutron stars in low mass X-ray binaries. Hard X-ray components extending up to energies of a few hundred keV have been clearly detected in…
Centaurus X-3 is a persistent high-mass X-ray binary with the long-term light curve from the source exhibiting orbit-to-orbit intensity variations with no apparent superorbital periodicity. We used $\sim$13.5 years of MAXI/GSC data to study…
We report on a multiwavelength observational campaign of the black hole X-ray binary Swift J1753.5-0127 that consists of an ESO/X-shooter spectrum supported by contemporaneous Swift/XRT+UVOT and ATCA data. ISM absorption lines in the…
We present intermediate resolution spectroscopy of the optical counterpart to the black hole X-ray transient MAXI J1820+070 (=ASASSN-18ey) obtained with the OSIRIS spectrograph on the 10.4-m Gran Telescopio Canarias. The observations were…
We present new optical and {\it Chandra} observations of the field containing the ultraluminous X-ray source NGC 1313 X-2. On an ESO 3.6 m image, the {\it Chandra} error box embraces a $R=21.6$ point-like object and excludes a previously…
By cross-matching the eclipsing binary catalog from TESS with that from LAMOST MRS, semi-detached eclipsing binaries with radial velocities coverage spanning more than 0.3 phases were authenticated. The absolute parameters for these systems…
We study the X-ray variability of SS433 based on data from the ASCA observatory and the MAXI and RXTE/ASM monitoring missions. Based on the ASCA data, we have constructed the power spectrum of SS433 in the frequency range from $10^{-6}$ to…
We present a method for the calculation of the effects of external irradiation on the geometrical shape of the secondary in a close binary containing a compact star, the source of the radiation, and a normal companion star, where we include…
The Chandra X-ray Observatory (CXO) imaged the high-mass gamma-ray binary (HMGB) HESS J0632+057 with the Advanced CCD Imaging Spectrometer (ACIS). We analyzed the CXO data together with 967 ks of archival Swift-XRT observations. On…
We derive the absolute physical and orbital parameters for a sample of 18 detached eclipsing binaries from the \emph{All Sky Automated Survey} (ASAS) database based on the available photometry and our own radial velocity measurements. The…
A correlation of X-ray source and Halpha emission-line object catalogues in the Small Magellanic Cloud (SMC) shows that more than two thirds of the optically identified Be stars in Be/X-ray binaries are found as emission-line objects in the…
We have studied the very long-term temporal properties of the optical emission from Be X-ray binaries (BeX) in the Small Magellanic Cloud over a ~ 16 yr baseline, using light curves from the MACHO and OGLE databases. All the BeX in our…
In solar flares, inverse Compton scattering (ICS) of photospheric photons might give rise to detectable hard X-ray photon fluxes from the corona where ambient densities are too low for significant bremsstrahlung or recombination. Gamma-ray…