Theory of Low-Mass Stars and Substellar Objects

  title={Theory of Low-Mass Stars and Substellar Objects},
  author={Gilles Chabrier and Isabelle Baraffe},
  journal={Annual Review of Astronomy and Astrophysics},
▪ Abstract Since the discovery of the first bona-fide brown dwarfs and extra-solar planets in 1995, the field of low-mass stars and substellar objects has progressed considerably, both from theoret... 
Brown dwarfs: Failed stars, super jupiters
The recently discovered brown dwarfs that bridge the gap between giant planets and hydrogen-fusing stars are enabling unique insights into low-temperature atmospheres, star and planet formation, and
From the Sun to Jupiter: Evolution of Low Mass Stars and Brown Dwarfs down to Planetary Masses
We present current models for low mass stars and substellar objects down to planetary masses and discuss the success and remaining uncertainties of the theory. We focus on early evolutionary phases
Evolutionary Models for Low Mass Stars and Brown Dwarfs at Young Ages
We analyse evolutionary tracks at young ages for low mass stars with masses m :S 1.4 M0 and brown dwarfs down to one mass of Jupiter. We analyse current theoretical uncertainties due to initial
The search for M-M Dwarf Eclipsing Binary Systems
An account of our search for, and discovery of an M-M Dwarf Eclipsing Binary system, the second brightest known, in an effort to provide more data to the literature in the hope of using this data set
Ultracool Objects: L, T, and Y Dwarfs
The discovery of the first bona fide brown dwarfs in 1995 ushered in a new era in both stellar and planetary astrophysics. The emergent spectra of brown dwarfs are distinct from those of the
Star Formation in the Milky Way and Nearby Galaxies
We review progress over the past decade in observations of large-scale star formation, with a focus on the interface between extragalactic and Galactic studies. Methods of measuring gas contents and
Chemistry of Low Mass Substellar Objects
“Brown dwarfs” is the collective name for objects more massive than giant planets such as Jupiter but less massive than M dwarf stars. This review gives a brief description of the classification and
Atmospheres From Very Low-Mass Stars to Extrasolar Planets
Within the next few years, several instruments aiming at imaging extrasolar planets will see first light. In parallel, low mass planets are being searched around red dwarfs which offer more favorable
Discovery Of A Low-Mass Companion To The Solar-Type Star Tyc 2534-698-1
Brown dwarfs and low-mass stellar companions are interesting objects to study since they occupy the mass region between deuterium and hydrogen burning. We report here the serendipitous discovery of a
High Energy Densities in Planets and Stars
In this chapter we consider—from the standpoint of high energy density physics—the processes and phenomena that take place inside cosmic objects compressed by gravitational forces to compact


Evolution of very low mass stars and brown dwarfs. I. The minimum main-sequence mass and luminosity.
We performed some numerical computations on the evolution of objects having masses close to the limiting mass for the onset of stable hydrogen burning, for Population I chemical composition (Y =
Theoretical models of low-mass stars and brown dwarfs. I. The lower main sequence
Theoretical models are calculated for stars on the hydrogen-burning lower main sequence having masses less than or equal to 0.55 solar mass. Particular attention has been paid to the treatment of the
Spectral Evidence for Dust in Late-Type M Dwarfs
We draw attention to the 0.65-0.75 μm region of the spectra of late-type M dwarfs, where we find that the Ti0 molecular absorption bonds decrease rather than increase in strength toward later
A Jupiter-mass companion to a solar-type star
The presence of a Jupiter-mass companion to the star 51 Pegasi is inferred from observations of periodic variations in the star's radial velocity. The companion lies only about eight million
The Structure of Stars of Very Low Mass.
Completely convective models were constructed for stars of masses 0.09, 0.08, 0.07, 0.06, 0.05, and 0.04 (solar units), taking into account the non- relativistic degeneracy of the stellar material.
Star Formation in Molecular Clouds: Observation and Theory
Star-formation (SF) processes occurring on the scale of giant molecular clouds (10 to the 6th solar masses and 10 to the 20th cm) or smaller are discussed, reviewing the results of recent theoretical
An expanded set of brown dwarf and very low mass star models
We present in this paper updated and improved theoretical models of brown dwarfs and late M dwarfs. The evolution and characteristics of objects between 0.01 and 0.2 solar mass are exhaustively
The HR Diagram and the Galactic Distance Scale After Hipparcos
▪ Abstract The completion and publication of the Hipparcos astrometric catalogue has revitalized studies in many fundamental areas of Galactic structure and stellar evolution. This article reviews
Rotational Velocities and Chromospheric/Coronal Activity of Low-Mass Stars in the Young Open Clusters IC 2391 and IC 2602
We have obtained high-resolution, moderate signal-to-noise ratio spectra for approximately 80 candidate low-mass members of the nearby, very young open clusters IC 2391 and IC 2602. Most of the stars
Structure and evolution of low-mass stars
We present extensive calculations of the structure and the evolution of low-mass stars in the range 0.07-0.8 M, for metallicities 2:0 (M=H) 0:0. These calculations are based on the most recent