Related papers: Identifying quiescent compact objects in massive G…
It is now well established that a large fraction of the low-mass stars are binaries or higher order multiples. Similarly a sizable fraction have giant planets. In contrast to these, the situation for brown dwarf companions is complicated:…
Binaries play a critical role in the formation, evolution, and fundamental properties of planets, stars, and stellar associations. Observational studies in these areas often include a mix of observations aimed at detecting or ruling out the…
Eclipsing binary star systems provide the most accurate method of measuring both the masses and radii of stars. Moreover, they enable testing tidal synchronization and circularization theories, as well as constraining models of stellar…
TESS has proven to be a powerful resource for finding planets, including those that orbit the most prevalent stars in our galaxy: the M dwarfs. Identification of stellar companions (both bound and unbound) has become a standard component of…
The detection of O- and B-type stars with extremely low-mass companions is very important for understanding the formation and evolution of binary stars. However, their finding remains a challenge because the low-mass components in such…
The results of speckle interferometric observations of 104 binary and 6 triple stars performed at the BTA 6 m telescope in 2004 October are presented. Nearby low-mass stars are mostly observed for the program, among which 59 there are new…
Red supergiants (RSGs), as the descendants of OB-type stars and the progenitors of supernovae, provide crucial insights into the evolution of massive stars, particularly in binary systems. Previous studies show that the binary fraction of…
Abridged. Eclipsing spectroscopic double-lined binaries are the prime source of precise and accurate measurements of masses and radii of stars. These measurements provide a stringent test of models of stellar evolution that are persistently…
The latest results from our ongoing multiplicity study of (Community) TESS Objects of Interest are presented, using astro- and photometric data from the ESA-Gaia mission, to detect stellar companions of these stars and characterize their…
The time-domain (TD) surveys of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) yield high-cadence radial velocities, paving a new avenue to study binary systems including compact objects. In this work, we explore…
We present high resolution Laser Guide Star Adaptive Optics imaging of 43 late-M, L and T dwarf systems with Keck/NIRC2. These include 17 spectral binary candidates, systems whose spectra suggest the presence of a T dwarf secondary. We…
A fraction of Galactic stars have compact companions which could be white dwarfs (WDs), neutron stars (NSs) or stellar-mass black holes (SBHs). In a detached and edge-on binary system including a main-sequence star and a compact object…
The origin of rapid rotation in massive stars remains debated, although binary interactions are now often advocated as a cause. However, the broad and shallow lines in the spectra of fast rotators make direct detection of binarity…
Context. Although more than one thousand sub-stellar companions have already been detected with the radial velocity (RV) method, many new companions remain to be detected in the public RV archives. Aims. We wish to use the archival data…
Time-domain (TD) spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) can provide accurate and high-cadence radial velocities (RVs). In this work, we search for binaries with compact components with…
In this paper we present the latest results of our ongoing multiplicity survey of (Community) TESS Objects of Interest, using astrometry and photometry from the latest data release of the ESA Gaia mission to detect stellar companions of…
We present and discuss initial selection criteria and first results in M33 from a systematic search for extragalactic symbiotic stars. We show that the presence of diffuse interstellar gas emission can significantly contaminate the spectra…
We present results of a high angular resolution survey of massive OB stars in the Cygnus OB2 association that we conducted with the NIRI camera and ALTAIR adaptive optics system of the Gemini North telescope. We observed 74 O- and early…
The first results of a new survey are reported, which explores the 2nd data release of the ESA-Gaia mission, in order to search for stellar companions of (Community) TESS Objects of Interest and to characterize their properties. In total,…
Symbiotic stars are among the most crucial binary systems for studying binary star interactions and Type Ia supernova progenitors. Based on the unique observational characteristics of symbiotic stars, strong H I, He I emission lines, giant…