Related papers: Coaxing the Eclipsing Binary V367 Cygni Out of Its…
Following on our initial absorption-line analysis of fifteen novae spectra we present additional evidence for the existence of two distinct components of novae ejecta having different origins. As argued in Paper I one component is the…
(Abridged) We present a comparative analysis of the galaxy emission and QSO absorption kinematics of a z~0.7450 MgII system and its candidate absorbing galaxy (G5) located 3.86 arcsecs (28.3 h-1 kpc) from the QSO. We have obtained a…
We report on FORS2 optical spectroscopy of the black hole X-ray binary V404 Cygni, performed at the very beginning of its 2015 outburst decay, complemented by quasi-simultaneous $Swift$ X-ray and ultra-violet as well as REM near-infrared…
(abridged) The high-resolution X-ray spectrum of NGC 3783 shows several dozen absorption lines and a few emission lines from the H-like and He-like ions of O, Ne, Mg, Si, and S as well as from Fe XVII - Fe XXIII L-shell transitions. We have…
Some evidences of wind variability and velocity stratification in the extended atmosphere has been found in the spectra of the supergiant V340 Ser (=IRAS 17279$-$1119) taken at the 6-m BTA telescope with a spectral resolution R$\ge$60000.…
The optical light of the symbiotic binary BF Cygni during its last eruption after 2006 shows orbital variations because of an eclipse of the outbursting compact object. The first orbital minimum is deeper than the following ones. Moreover,…
We present near-infrared and optical observations of the nova V496 Scuti 2009 covering various phases - pre-maximum, early decline and nebular - during the first 10 months of its discovery followed by limited observations in early part of…
Numerous white dwarf stars are known to be orbited by disks of gas and dust. To date, broad, about 300 km s-1 wide, gaseous circumstellar absorption features have only been reported for the already iconic WD 1145+017, where one is…
We have carried out a detailed analysis of the IUE archival high resolution spectra of the classical nova V1974 Cyg 1992. In addition to the P Cygni and emission lines, two shortward shifted absorption systems are present. Evidence is given…
We present new results of a spectroscopic survey of circumstellar HI in the direction of evolved stars made with the Nancay Radiotelescope. The HI line at 21 cm has been detected in the circumstellar shells of a variety of evolved stars:…
We present a study of the morphology of the ejecta in Supernova 1987A based on images and spectra from the HST as well as integral field spectroscopy from VLT/SINFONI. The HST observations were obtained between 1994 - 2011 and primarily…
We determine the age of the eclipsing binary V380 Cygni, whose components have a significant mass ratio, $M_B/M_A\approx$ 0.6. Because this binary exhibits spectral lines of both components, the values of masses and radii could be…
We present a phase-resolved, optical, spectroscopic study of the eclipsing low-mass X-ray binary, EXO 0748-676 = UY Vol. The sensitivity of Gemini combined with our complete phase coverage makes for the most detailed blue spectroscopic…
(Abridged) We present spectroscopic and photometric observations of the eclipsing system V1061 Cyg (P = 2.35 days). We show that it is a hierarchical triple in which the third star is visible in the spectra. We combine the radial velocities…
Supernova observations imply the presence of a dense and asymmetric circumstellar environment around SN Type II progenitors, whereas the mass loss from these progenitors, namely, red supergiants, is still poorly constrained. We aim to…
The luminous X-ray binary Circinus X-1 has been observed twice near zero orbital phase using the High-Energy Transmission Grating Spectrometer (HETGS) onboard Chandra. The source was in a high-flux state during a flare for the first…
We report the results of high-resolution ($R \sim 80,000$) spectroscopic observations of the emission-line object HD 85567, which has been classified as a FS CMa type object or a pre-main-sequence star. The main goal is to put more…
Based on high-resolution spectroscopy performed with the NES echelle spectrograph of the 6-m telescope, we have studied the peculiarities of the spectrum and the velocity field in the atmosphere and envelope of the cool supergiant V1027…
We present a detailed analysis and interpretation of the high-mass binary V380 Cyg, based on high-precision space photometry gathered with the Kepler space mission as well as high-resolution ground-based spectroscopy obtained with the…
As one of the best-characterized stellar-mass black holes, with good measurements of its mass, distance and inclination, V404 Cyg is the ideal candidate to study Eddington-limited accretion episodes. After a long quiescent period, V404 Cyg…