New Evolutionary Tracks for Very Low Mass Stars

Abstract

view Abstract Citations (133) References (20) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS New Evolutionary Tracks for Very Low Mass Stars Baraffe, I. ; Chabrier, G. ; Allard, F. ; Hauschildt, P. H. Abstract We present new evolutionary calculations for low-mass and very low mass M dwarfs, for a metallicity range -2 ≤ [M/H] ≤ 0, down to the hydrogen-burning minimum mass (0.07 < M/Msun < 0.6). We use the most recent atmosphere models calculated by Allard & Hauschildt (1995), based on synthetic spectra at finite metallicity, and gray atmosphere models based on Alexander & Ferguson (1994) Rosseland opacities. Comparisons are made with observational results down to the bottom of the main sequence, for different metallicities, in magnitude-color and color-color diagrams. We find excellent agreement between theory and observations over the whole characteristic temperature/luminosity range. This enables us to determine the mass of the faintest objects observed, which is found to be mlim ≍ 0.085 Msun for [M/H] = 0 and -0.5, and mlim = 0.09 Msun for [M/H] = -1.5, for an age of 10 Gyr. We also examine the effect of the age, the metallicity, and the outer boundary conditions on the evolution. Publication: The Astrophysical Journal Pub Date: June 1995 DOI: 10.1086/187924 Bibcode: 1995ApJ...446L..35B Keywords: STARS: LOW-MASS; BROWN DWARFS; STARS: EVOLUTION; STARS: LATE-TYPE full text sources ADS | data products SIMBAD (2)