Related papers: IR spectroscopy of pre-cataclysmic binaries
We focus on short--period eclipsing binaries that belong to a class of Cataclysmic Variables (CVs). They are known as polars and intermediate polars, closely resembling their prototype AM Herculis. These binaries consist of a red dwarf and…
Detection of electromagnetic (EM) counterparts of pre-coalescence binaries has very important implications for our understanding of the evolution of these systems as well as the associated accretion physics. In addition, a combination of EM…
Although the study of X-ray binaries has led to major breakthroughs in high-energy astrophysics, their circumbinary environment at scales of $\sim$100--10,000 astronomical units has not been thoroughly investigated. In this paper, we…
We study the evolution of the normalized flux of selected ultraviolet emission lines of three classical novae (PW Vul, V1668 Cyg and V1974 Cyg). Different phases ofthe outbursts are studied. We attribute the spectral behavior of the three…
Aims. We analyze new multicolor light curves and recently published radial velocity curves for close binaries QX And, RW Com, MR Del, and BD +07{\circ} 3142 to determine the physical parameters of the components. Methods. The light curves…
In this paper, the historical infrared (JHK) data compiled from the published literature are presented in electronic form for 40 radio selected BL Lacertae objects (RBLs) for the first time. Largest variations are found and compared with…
We report follow-up studies of 35 recently-discovered cataclysmic variables (CVs), 32 of which were found in large, automated synoptic sky surveys. The objects were selected for observational tractability. For 34 of the objects we present…
We present JHK-band near-infrared photometry of star clusters in the dwarf irregular galaxy IC 5152. After excluding possible foreground stars, a number of candidate star clusters are identified in the near-infrared images of IC 5152, which…
A comparative study of spectra of 21 Type Ia supernovae (SNe Ia) obtained about one week before maximum light, and 8 spectra obtained 11 or more days before maximum, is presented. To a large extent the premaximum spectra exhibit the…
Wide binaries, with separations between two stars from a few AU to more than several thousand AU, are valuable objects for various research topics in Galactic astronomy. As the number of newly reported wide binaries continues to increase,…
We present near-infrared (NIR) spectra for Type Ia supernovae at epochs of 13 to 338 days after maximum blue light. Some contemporary optical spectra are also shown. All the NIR spectra exhibit considerable structure throughout the J-, H-…
We present some preliminary results from recent numerical simulations that model the evolution of super-massive black hole (SMBH) binaries in galactic nuclei. Including the post-Newtonian terms for the binary system and adopting appropriate…
We present the results of spectroscopic-- and orbit--sampled photometric observations of the faint UV-excess object PG 2200+085. The optical CCD photometry observations of this object were performed by the Russian-Turkish 1.5-meter…
Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the sixth set of ten close binary systems: SV Cam, EE Cet, KR Com, V410 Cyg, GM Dra, V972 Her, ET Leo, FS Leo, V2388 Oph, II UMa. All…
Gamma-ray binaries allow us to study physical processes such as particle acceleration up to very-high energies and gamma-ray emission and absorption with changing geometrical configurations on a periodic basis. These sources produce…
We present the results of our search for optical counterparts to high-mass X-ray transient sources discovered by various X-ray missions. We obtained CCD images of the X-ray fields through BVR and Halpha filters in order to identify…
We compare waveforms and orbital dynamics from the first long-term, fully non-linear, numerical simulations of a generic black-hole binary configuration with post-Newtonian predictions. The binary has mass ratio q~0.8 with arbitrarily…
We report the discovery of very-high-energy (VHE) gamma-ray emission of the binary system PSR B1259-63/SS 2883 of a radio pulsar orbiting a massive, luminous Be star in a highly eccentric orbit. The observations around the 2004 periastron…
Cataclysmic variables (CVs) are binaries in which a compact white dwarf accretes material from a low-mass companion star. The discovery of two planets in orbit around the CV HU Aquarii opens unusual opportunities for understanding the…
We report the identification of 17 candidate brown dwarf binaries whose components straddle the L dwarf/T dwarf transition. These sources were culled from a large near-infrared spectral sample of L and T dwarfs observed with the Infrared…