Early-type stars in the young open cluster NGC 2244 and in the Monoceros OB2 association. I. The mul

  title={Early-type stars in the young open cluster NGC 2244 and in the Monoceros OB2 association. I. The mul},
  author={Laurent Mahy and Ya{\"e}l Naz{\'e} and Gregor Rauw and Eric Gosset and Micha{\"e}l De Becker and Hugues Sana and Philippe R. J. Eenens},
  journal={Astronomy and Astrophysics},
Aims. We present the results obtained from a long-term spectroscopic campaign devoted to the multiplicity of O-type stars in the young open cluster NGC 2244 and in the Mon OB2 association. Methods. Our spectroscopic monitoring was performed over several years, allowing us to probe different time-scales. For each star, several spectral diagnostic tools are applied, in order to s earch for line shifts and profile variations. We also measure the projected rotational velocity and revisit the… 

A spectroscopic investigation of early-type stars in the young open cluster Westerlund 2

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A quantitative study of O stars in NGC 2244 and the Monoceros OB2 association

Aims. Our goal is to determine the stellar and wind properties of seven O stars in the cluster NGC 2244 and three O stars in the OB association Mon OB2. These properties give us insight into the mass


With an orbital period of about 3.078 days, the double-lined spectroscopic binary HD 48099 is, until now, the only short-period O+O system known in the Mon OB2 association. Even though an orbital

The young massive SMC cluster NGC 330 seen by MUSE

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NGC 2244 located in the Rosette Nebula is a young open cluster composed of seven O-type stars. A first paper focused on the multiplicity of these stars, revealed only one binary system out of the

Variability in the CoRoT photometry of three hot O-type stars HD 46223, HD 46150, and HD 46966

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MONOS: Multiplicity Of Northern O-type Spectroscopic systems. II. Orbit review and analysis for 35 single-lined spectroscopic binary systems and candidates.

Context. Multiplicity in massive stars is key to understanding the chemical and dynamical evolution of galaxies. Among massive stars, those of O type play a crucial role due to their high masses and



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We present the results of a long-term high-resolution spectroscopy campaign on the O-type stars in NGC 6231. We revise the spectral classification and multiplicity of these objects and we constrain

Early-type stars in the young open cluster IC 1805. II. The probably single stars HD 15570 and HD 15629, and the massive binary/triple system HD 15558

Aims. We address the issue of the multiplicity of the three brightest early-type stars of the young open cluster IC 1805, namely HD 15570, HD 15629 and HD 15558. Methods. For the three stars, we

Radial-velocity measurements in 20 young open clusters

The further results of a program to determine the radial velocities of young open clusters are presented. Using the KPNO coude spectrograph coupled with the 1-m feed and 2.1-m telescopes, radial

A Chandra Study of the Rosette Star-forming Complex. I. The Stellar Population and Structure of the Young Open Cluster NGC 2244

We present the first high spatial resolution X-ray study of NGC 2244, the 2 Myr old stellar cluster in the Rosette Nebula, using Chandra. Over 900 X-ray sources are detected; 77% have optical or

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We present a study aimed at clarifying the birthplace for 43 massive O-type field stars. In this first paper we present the observational part: a search for stellar clusters near the target stars. We

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In this second paper of the series, we pursue the analysis of the 180-ks XMM‐Newton campaign towards the young open cluster NGC 6231 and we focus on its rich OB star population. We present a

Mass Segregation in Very Young Open Clusters: A Case Study of NGC 2244 and NGC 6530

We derive the proper motions, membership probabilities, and velocity dispersions of stars in the regions of the young (similar to 2 - 4 Myr old) open clusters NGC 2244 ( the central cluster in the

Fourier method of determining the rotational velocities in OB stars

Aims. We present a comprehensive study that applies the Fourier transform to a sample of O and early B-type stars (either dwarfs, giants, or supergiants) to determine their projected rotational

Spectroscopic studies of O-type stars. VIII - Radial velocities and the K-term

Radial velocities are measured on coude spectrograms of over 200 O-type stars in both hemispheres. The selection of effective wavelengths for the stellar lines to be measured is reviewed, and the