88 datasets found

We have obtained multi-epoch observations of 31 O-type stars in the Carina Nebula using the CHIRON spectrograph on the CTIO/SMARTS 1.5-m telescope. We measure their radial...

Using an extended set of multi-epoch high resolution high signal-to-noise ratio optical spectra, we re-address the multiplicity properties of the O-type stars in IC 2944 and in...

The central parsec around the supermassive black hole in the Galactic center (GC) hosts more than 100 young and massive stars. Outside the central cusp (R~1") the majority of...

Stellar kinematics provides the key to understanding the star formation process. In this respect, we present a kinematic study of the Monoceros OB1 (Mon OB1) and R1 (Mon R1)...

We present radial velocities for 18 Galactic O-type stars. These stars display small radial velocity scatter over timescales of one to two weeks. Some of them are long-period...

Our long-term aim is to derive model-independent stellar masses and distances for long period massive binaries by combining apparent astrometric orbit with double-lined radial...

Theoretically, rotation-induced chemical mixing in massive stars has far reaching evolutionary consequences, affecting the sequence of morphological phases, lifetimes,...

The Tarantula region in the Large Magellanic Cloud contains the richest population of spatially resolved massive O-type stars known so far. This unmatched sample offers an...

Establishing the multiplicity of O-type stars is the first step towards accurately determining their stellar parameters. Moreover, the distribution of the orbital parameters...

The Tarantula Nebula in the Large Magellanic Cloud is our closest view of a starburst region and is the ideal environment to investigate important questions regarding the...

Reliable systemic radial velocities are almost impossible to secure for Wolf-Rayet stars, difficult for O stars. Therefore, to study the motions - both systematic in the Galaxy...

We present simultaneous observations of several rotational lines of ^28^SiO in the v=1, 2, 3, and 4 vibrationally excited states toward O-rich evolved stars. All the data were...

We have produced a catalog of 378 Galactic O stars with accurate spectral classifications that is complete for V<8 but includes many fainter stars. The catalog provides...

The sample of 37485 suspected OB stars selected by Gontcharov (2008AstL...34....7G) from the Tycho-2 catalogue has been cleaned of the stars that are not of spectral types...

We present the JHKLM photometry for 22 hot stars, 11 of which were identified in the GCVS. For all of the observed objects, we have estimated the interstellar reddening, angular...

This investigation presents a study of the Galactic structure toward the Norma section of the Milky Way. The field studied is located between 325{deg} and 335{deg} Galactic...

The presence of a nearby companion alters the evolution of massive stars in binary systems, leading to phenomena such as stellar mergers, X-ray binaries and gamma-ray bursts....

The morphology and kinematics of the spiral structure of the Milky Way are long-standing problems in astrophysics. In this review we firstly summarize various methods with...

The Lynds' Dark Nebula (LDN) 1615/1616 and CB 28 (hereafter L1616) together form a cometary globule located at an angular distance of about 8{deg} west of the Orion OB1...

In this paper, we describe an analysis of the MiMeS (Magnetism in Massive Stars) survey of O-type stars to explore the range of dipolar field strengths permitted by the...