Spectroscopic identification of DENIS-selected brown dwarf candidates in the Upper Scorpius OB association

Details Spectroscopic identification of DENIS-selected brown dwarf candidates in the Upper Scorpius OB association Spectroscopic identification of DENIS-selected brown dwarf candidates in the Upper Scorpius OB association

2003-10-29

arxiv.org/abs/astro-ph/0310819v1

Astronomy and Astrophysics

Astrophysics

Accepted for publication in The Astronomical Journal, January 2004

Scientific paper

10.1086/380226

We present low-resolution (R=900) optical (576.1--1,051.1 nm) spectroscopic observations of 40 candidate very low-mass members in the Upper Scorpius OB association. These objects were selected using the $I$, $J$ and $K$ photometry available in the DENIS database. We have derived spectral types and we have measured H$\alpha$ and NaI doublet (at 818.3 and 819.5 nm) equivalent widths. We assess the youth of the objects by comparing them to their older counterparts of similar spectral type in the Pleiades cluster and the field. Our analysis indicates that 28 of our targets are young very low-mass objects, and thus they are strong candidate members of the OB association. The other 12 DENIS sources are foreground M dwarfs or background red giants. Our sample of spectroscopic candidate members includes 18 objects with spectral types in the range M6.5 and M9, which are likely young brown dwarfs. We classify these candidates as accreting/non accreting using the scheme proposed by Barrado y Navascu\'es & Mart\'\i n (2003). We find 5 substellar-mass candidate cluster members that are still undergoing mass accretion, indicating that the timescale for accretion onto brown dwarfs can be as long as 5 Myr in some cases.

Affiliated with

Also associated with

No associations

Rating

Spectroscopic identification of DENIS-selected brown dwarf candidates in the Upper Scorpius OB association does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spectroscopic identification of DENIS-selected brown dwarf candidates in the Upper Scorpius OB association, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectroscopic identification of DENIS-selected brown dwarf candidates in the Upper Scorpius OB association will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-199214