Related papers: Spectroscopic binaries among Hipparcos M giants II…

A catalog of 383 radial velocities for red giants in the globular cluster M22 has been compiled from the literature and from new observations accumulated between 1972 and 1994. This 22-year baseline is the longest available for any sample…

We re-determine planetary occurrences around M dwarfs using 20 years of observations from HARPS on 197 targets. The first aim of this study is to propose more precise occurrence rates using the large volume of the sample but also variations…

Some pulsating stars are good clocks. When they are found in binary stars, the frequencies of their luminosity variations are modulated by the Doppler effect caused by orbital motion. For each pulsation frequency this manifests itself as a…

We present the first search for binary companions of Massive Young Stellar Objects (MYSOs) using AO-assisted $K$ band observations, with NaCo at the VLT. We have surveyed 32 MYSOs from the RMS catalogue, probing the widest companions, with…

We present a method for finding binaries among pulsating stars that were observed by the Kepler Mission. We use entire four-year light curves to accurately measure the frequencies of the strongest pulsation modes, then track the pulsation…

We present a large multi-epoch high resolution spectroscopic investigation for the search of binary candidates in the Galactic Globular Cluster (GGC) M4. The aim of our work is the identification of the binary candidates, and the…

Despite their key role in astrophysics, the binary properties of RR Lyrae stars (RRL) remain almost completely unknown since only a single RRL is confirmed as belonging to a binary system. Finding companions to RRL is difficult since most…

Within the context of the collaboration "B fields in OB stars (BOB)", we used the FORS2 low-resolution spectropolarimeter to search for a magnetic field in 50 massive stars, including two reference magnetic massive stars. Because of the…

Red subdwarfs in binary systems are crucial for both model calibration and spectral classification. We search for red subdwarfs in binary systems from a sample of high proper motion objects with Sloan digital Sky Survey spectroscopy. We…

We identify a sample of near-equal mass wide binary M dwarf systems from the SLoWPoKES catalog of common proper-motion binaries and obtain follow-up observations of their chromospheric activity as measured by the H$\alpha$ emission line. We…

We report on a data-driven spectral model that we have developed for the identification of double-lined spectroscopic binary stars (SB2s) in the LAMOST low-resolution survey (R$\sim$1800). Employing simultaneous fitting with both…

We present preliminary results of a radial-velocity search for companions to a volume limited sample of M dwarfs. Typical accuracy range between 10m/s for the brighter stars and 70m/s at our limiting magnitude. We complement the radial…

Context: A radial velocity survey of about 380 G and K giant stars is ongoing at Lick observatory. For each star we have a high signal to noise ratio template spectrum, which we use to determine spectroscopic stellar parameters. Aim: The…

We present high-resolution echelle spectroscopy of 676 nearby M dwarfs. Our measurements include radial velocities, equivalent widths of important chromospheric emission lines, and rotational velocities for rapidly rotating stars. We…

(Abbreviated) We have used precise radial velocity measurements of subdwarf-B stars from the Palomar-Green catalogue to look for binary extreme horizontal branch (EHB) stars. We identify 36 EHB stars in our sample and find that at least 21…

It is believed that the radio pulsars rotating at spin periods of about 30 millisecond or even lower got such high spins through the transfer of angular momentum by accreting matter from their binary companions (or past companions) in the…

Eclipsing binaries are vital for directly determining stellar parameters without reliance on models or scaling relations. Spectroscopically derived parameters of detached and semi-detached binaries allow us to determine component masses…

We study the fast rotating M5 giant EK Boo by means of spectropolarimetry to obtain direct and simultaneous measurements of both the magnetic field and activity indicators, in order to infer the origin of the activity in this fairly evolved…

We report the discovery of 24 spectroscopic binary companions to giant stars. We fully constrain the orbital solution for 6 of these systems. We cannot unambiguously derive the orbital elements for the remaining stars because the phase…

Stellar activity and rotation frustrate the detection of exoplanets through the radial velocity technique. This effect is particularly of concern for M dwarfs, which can remain magnetically active for billions of years. We compile rotation…