157 datasets found

The process of massive star (M>=8M_{sun}) formation is still poorly understood. Observations of massive young stellar objects (MYSOs) are challenging due to their rarity,...

The evolution of massive stars is strongly influenced by internal mixing processes such as semiconvection, convective core overshooting, and rotationally induced mixing. None of...

Stars which start their lives with spectral types O and early-B are the progenitors of core-collapse supernovae, long gamma-ray bursts, neutron stars, and black holes. These...

The interplay between the formation of stars, stellar feedback and cloud properties strongly influences the star formation history of giant molecular clouds. The formation of...

While it is currently unclear from a theoretical standpoint which forces and processes dominate the formation of high-mass stars, and hence determine the mode in which they...

Photospheric lines of B-type supergiants show variability in their profile shapes. In addition, their widths are much wider than can be accounted for purely by stellar rotation....

Star-forming complexes are large structures exhibiting massive star-formation at different stages of evolution, from dense cores to well-developed HII regions. They are very...

We present the results of an X-ray campaign towards the young open cluster NGC 6231. The XMM-Newton observations, of a total duration of about 180 ks, reveals that NGC 6231 is...

To investigate the dependence of (visual) binarity characteristics on the primary component mass, we selected all stars of spectral type B in Sco OB2 association and searched...

In this paper the mass of the neutron star in Vela X-1 is determined, by measuring the radial velocity curve of its B supergiant companion. The tables (appendix of the paper),...

About 700 stars, mostly OB-stars, were observed by the author at the former Leiden Southern Station at Hartebees poortdam, South Africa, in the observing seasons 1965, 1968,...

The catalog is a compilation of MK spectral types published in the paper, "The kinematics of the Gould Belt: An Expanding Group?" (Rountree Lesh 1968). Spectral types were...

The Atlas provides digital spectra to assist the classification of OB spectra for 78 standard objects in the wavelength range 395.0-475.0 nm. Spectral types range from O3 - B3...

A catalog of the O-B stars, selected from "Blaauw-Parenago" list (1955, First IAU Symposium, "Co-ordination of galactic research") and Rubin's catalog (1962AJ.....67..491R, Cat....

A new partition into associations of OB stars within 3kpc of the Sun is derived using Battinelli's modification of the cluster analysis method. We have found 58 associations, of...

Spectra from the Flash and Heros Echelle spectrographs developed at Landessternwarte Heidelberg and mounted at La Silla and various other observatories. The data mostly contains...

Spectra from the Flash and Heros Echelle spectrographs developed at Landessternwarte Heidelberg and mounted at La Silla and various other observatories. The data mostly contains...

Spectra from FEROS spectrograph at La Silla's 1.5m telescope as obtained during commissioning and guaranteed time.

We calculated the median parallaxes for 47 OB associations including at least 10 stars with known Gaia DR2 parallaxes. A comparison between trigonometric and photometric...

We aim to determine the physical properties of OB stars from the multi-epoch Binarity at LOw Metallicity (BLOeM) spectroscopic survey of the Small Magellanic Cloud using the...