6533b821fe1ef96bd127c23d
RESEARCH PRODUCT
A study of the B and Be star population in the field of the LMC open cluster NGC 2004 with VLT-FLAMES
Juan FabregatChristophe MartayanJean ZorecMichele FloquetCoralie NeinerPhilippe SteeAnne-marie HubertYves Frematsubject
Be starPopulationFOS: Physical sciencesAstrophysicsAstrophysicsUNESCO::ASTRONOMÍA Y ASTROFÍSICA01 natural sciencesbinaries: eclipsing [Stars]Spectral lineStars: early-type[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]ISM: nebular lines and bandsMagellanic Clouds [Galaxies]early-type [Stars]Stars: binaries: spectroscopic0103 physical sciencesCluster (physics)education010303 astronomy & astrophysicsStars: binaries: eclipsingPhysicseducation.field_of_study[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph]010308 nuclear & particles physicsStars: emission-lineAstrophysics (astro-ph)Stars: early-type ; Stars: emission-line Be ; Galaxies: Magellanic Clouds ; Stars: binaries: spectroscopic ; Stars: binaries: eclipsing ; ISM: lines and bandsAstronomy and AstrophysicsBeGalaxies: Magellanic CloudsGalaxyRadial velocityStarsbinaries: spectroscopic [Stars]Space and Planetary Scienceemission-line Be [Stars][SDU]Sciences of the Universe [physics]lines and bands [ISM]:ASTRONOMÍA Y ASTROFÍSICA [UNESCO]Open clusterdescription
Observations of hot stars belonging to the young cluster LMC-NGC2004 and its surrounding region have been obtained with the VLT-GIRAFFE facilities in MEDUSA mode. 25 Be stars were discovered; the proportion of Be stars compared to B-type stars is found to be of the same order in the LMC and in the Galaxy fields. 23 hot stars were discovered as spectroscopic binaries (SB1 and SB2), 5 of these are found to be eclipsing systems from the MACHO database, with periods of a few days. About 75% of the spectra in our sample are polluted by hydrogen (Halpha and Hgamma), [SII] and [NII] nebular lines. These lines are typical of HII regions. They could be associated with patchy nebulosities with a bi-modal distribution in radial velocity, with higher values (+335 kms^{-1}) preferentially seen inside the southern part of the known bubble LMC4 observed in HI at 21 cm.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-09-13 |