Volume 420, Number 2, June III 2004
|Page(s)||647 - 653|
|Section||Stellar structure and evolution|
|Published online||28 May 2004|
Infrared spectroscopy of a brown dwarf companion candidate near the young star GSC 08047-00232 in Horologium*
Astrophysikalisches Institut, Universität Jena, Schillergäßchen 2-3, 07745 Jena, Germany
2 Thüringer Landessternwarte Tautenburg, Sternwarte 5, 07778 Tautenburg, Germany
Corresponding author: R. Neuhäuser, email@example.com
Accepted: 3 March 2004
We present infrared H- and K-band spectra of a companion candidate north of the young star GSC 08047-00232, a probable member of the nearby young Horologium association. From previously obtained JHK-band colors and the magnitude difference between primary and companion candidate, the latter could well be substellar (Neuhäuser et al. [CITE]) with the spectral type being roughly M 7-L 9 from the JHK colors (Chauvin et al. [CITE]). With the H- and K-band spectra now obtained with ISAAC at the VLT, the spectral type of the companion candidate is found to be M 6-9.5. Assuming the same age and distance as for the primary star ( Myr, 50 to 85 pc), this yields a mass of Jupiter masses for the companion, hence indeed substellar. After TWA-5 B and HR 7329 B, this is the third brown dwarf companion around a nearby (100 pc) young (100 Myr) star. A total of three confirmed brown dwarf companions (any mass, separation 50 AU) around 79 stars surveyed in three young nearby associations corresponds to a frequency of (with a correction for missing companions which are almost on the same line-of-sight as the primary star instead of being separated well), consistent with the expectation, if binaries have the same mass function as field stars. Hence, it seems that there is no brown dwarf desert at wide separations.
Key words: stars: late-type / stars: low-mass, brown dwarfs / stars: pre-main sequence
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.