New Brown Dwarfs and an Updated Initial Mass Function in Taurus
| dc.creator | Luhman, K. L. | |
| dc.date | 2004-11-16 | |
| dc.date | 2004-11-23 | |
| dc.date.accessioned | 2026-07-07T11:29:29Z | |
| dc.date.available | 2026-07-07T11:29:29Z | |
| dc.description | I have performed a search for young low-mass stars and brown dwarfs (BDs) in 2 regions encompassing a total area of 4 deg^2 in the Taurus star-forming region, discovering 15 new members of Taurus. In addition, I present 7 new members outside of these areas from the initial stage of a survey of all of Taurus. These 22 objects exhibit spectral types of M4.5-M9.25 and masses of 0.3-0.015 M_sun according to the theoretical evolutionary models of Baraffe and Chabrier, 7 of which are likely to be BDs. Emission in H(alpha), He I, Ca II, [O I], and [S II] and excess emission in optical and near-IR bands among some of these objects suggest the presence of accretion, outflows, and circumstellar disks. The results from the 4 deg^2 survey have been combined with previous studies of Taurus to arrive at an IMF for a total area of 12.4 deg^2. As in the previous IMFs for Taurus, the updated IMF peaks at a higher mass (0.8 M_sun) than the mass functions in IC 348 and Orion (0.1-0.2 M_sun). Meanwhile, the deficit of BDs in Taurus appears to be less significant (x1.4-1.8) than found in earlier studies (x2) because of a slightly higher BD fraction in the new IMF for Taurus and a lower BD fraction in the new spectroscopic IMF for the Trapezium from Slesnick and coworkers. The spatial distribution of the low-mass stars and BDs discovered in the two new survey areas closely matches that of the more massive members. Thus, on the degree size scales (~3 pc) probed to date, there is no indication that BDs form through ejection. | |
| dc.description | 35 pages, The Astrophysical Journal, 2004, v617 (December 20) | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0411447 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0411447 | |
| dc.identifier | Astrophys.J.617:1216-1232,2004 | |
| dc.identifier | doi:10.1086/425647 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/196728 | |
| dc.subject | Astrophysics | |
| dc.title | New Brown Dwarfs and an Updated Initial Mass Function in Taurus | |
| dc.type | text |