New Low-Mass Stars and Brown Dwarfs with Disks in Lupus

Details New Low-Mass Stars and Brown Dwarfs with Disks in Lupus New Low-Mass Stars and Brown Dwarfs with Disks in Lupus

2007-02-16

arxiv.org/abs/astro-ph/0702435v1

Astrophys.J.655:1095-1102,2007

Astronomy and Astrophysics

Astrophysics

18 pages, 3 tables, 6 figures

Scientific paper

10.1086/510363

Using the Infrared Array Camera and the Multiband Imaging Photometer aboard the {\it Spitzer Space Telescope}, we have obtained images of the Lupus 3 star-forming cloud at 3.6, 4.5, 5.8, 8.0, and 24 \micron. We present photometry in these bands for the 41 previously known members that are within our images. In addition, we have identified 19 possible new members of the cloud based on red 3.6-8.0 \micron colors that are indicative of circumstellar disks. We have performed optical spectroscopy on 6 of these candidates, all of which are confirmed as young low-mass members of Lupus 3. The spectral types of these new members range from M4.75 to M8, corresponding to masses of 0.2-0.03 $M_\odot$ for ages of $\sim1$ Myr according to theoretical evolutionary models. We also present optical spectroscopy of a candidate disk-bearing object in the vicinity of the Lupus 1 cloud, 2M 1541-3345, which Jayawardhana & Ivanov recently classified as a young brown dwarf ($M\sim0.03$ $M_\odot$) with a spectral type of M8. In contrast to their results, we measure an earlier spectral type of M5.75$\pm$0.25 for this object, indicating that it is probably a low-mass star ($M\sim0.1$ $M_\odot$). In fact, according to its gravity-sensitive absorption lines and its luminosity, 2M 1541-3345 is older than members of the Lupus clouds ($\tau\sim1$ Myr) and instead is probably a more evolved pre-main-sequence star that is not directly related to the current generation of star formation in Lupus.

Affiliated with

Also associated with

No associations

Rating

New Low-Mass Stars and Brown Dwarfs with Disks in Lupus 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 New Low-Mass Stars and Brown Dwarfs with Disks in Lupus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and New Low-Mass Stars and Brown Dwarfs with Disks in Lupus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-195970