Tinney The Bottom of the Main Sequence — And Beyond

Proceedings of the ESO Workshop Held in Garching, Germany, 10–12 August 1994
Erscheinungsjahr 2013
ISBN: 978-3-540-49217-7
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 309 Seiten, eBook

Reihe: ESO Astrophysics Symposia

The proceedings of this workshop should probably be prefaced with a few words on some of the more confusing jargon. The phrases "Very Low-Mass star" , "VLM star", or simply "VLM" are now used fairly uniformly by as tronomers studying the stars at the bottom of the hydrogen-burning stellar main sequence - unfortunately, however, there is no clear definition as to what constitutes a VLM star. The reader should be warned that VLM stars are variously considered to be stars with; masses less than 0.3M ; masses 0 less than 0.1M ; spectra later than about M6-7; luminosities fainter than 0 Mv = 15; or luminosities fainter than Mbol = 12. The important features of a VLM star, however, would seem to be (1) that it is about as faint as a star can be, and (2) that it still remains a star (ie. it still burns hydrogen) . All of the above criteria, therefore, would seem to qualify an object as a VLM star, and requiring a more stringent definition is probably quibbling.

Zielgruppe

Research

Autoren/Hrsg.

Tinney, Christopher G.

Inhaltsverzeichnis

I Modelling Very Low-Mass Stars and Brown Dwarfs.- The Quiet Lives of Very Low Mass Stars and Brown Dwarfs.- Luminosity Functions and the Mass Function.- The Evolution of Low-Mass Stars.- The Equation of State for the Interiors of Low-Mass Objects.- M (sub)Dwarf Model Atmospheres: The Next Generation.- Spectra and Colours of Brown Dwarfs.- II Surveys in the Field.- Photometric and Astrometric Surveys for Low-Mass Field Stars.- VLM Stars Toward the Barnard 5 Molecular Cloud.- Brown Dwarf Candidates from Digitally Stacked Schmidt Plates.- How Complete is Our Knowledge of the Nearby Stars?.- A Photographic Survey of the Southern Sky.- III Searches for Companions.- The Solar Neighbors in the Murky Depths of the Main Sequence.- A Search for Infrared Companions to White Dwarfs.- Two Faint Companions to the Nearby M-dwarf LHS1070.- Sub-arcsecond Imaging of G29–38 Using Adaptive Optics.- Brown Dwarfs and Planets Around Solar-type Stars: Searches by Precise Velocities.- SHARP Images of the Pre-main Sequence Star V536 Aquilae: A Binary with a Low-Mass Companion.- Exploration of the Lower Main Sequence Among Wide Binaries.- IV Observables.- The Temperature Scale for Cool Dwarfs.- Parallaxes and Absolute Magnitudes for VLM Stars.- Southern Stars Near the Substellar Boundary: An Update.- Classification Spectroscopy of M Dwarfs from 0.6 to 2.4 Microns.- The Design of the Low-Mass Binaries Database.- The Mass-Luminosity Relation for M-dwarfs.- Lithium and the Nature of Brown Dwarf Candidates.- V Very Low-Mass Stars and Brown Dwarfs in Clusters.- Star Formation and the Initial Mass Function.- Surveys of Nearby Clusters for Low-Mass Stars and Brown Dwarfs.- The VLM Main Sequence in Praesepe.- Near-infrared Observations of Low-Mass Objects in NGC 2024.- HST Photometry of Low-Mass Starsin Open Clusters.- Spectroscopy of M Type Stars in the ? Persei Open Cluster.- Low-Mass Stars and Brown Dwarfs in the Trapezium Cluster.- VI Activity.- Surface Activity and Rotation in Low-Mass Stars.- The Frequency of Magnetic Activity in Field M Dwarfs.- Chromospheric and Coronal Activity of Low-Mass Stars in the Pleiades.- Moderate Resolution Spectroscopy of VLM and BD-Candidate Members of the Pleiades and Hyades.- VII The Halo.- The Pop. II Lower Main Sequence: Some Properties and a Luminosity Function Determination.- Low-Mass Objects and the Dark Matter in the Halo.- Faint Companions to G/K Halo Subdwarfs.- On the Pop. II IMF: Many More Brown Dwarfs?.- Unveiling the IMF of Galactic Globular Clusters: the Case of NGC 1261.- A Review of Gravitational Microlensing Experiments.- VIII The Future in the Infrared.- VLM Stars and Brown Dwarfs from 2MASS and DENIS.- Searching for Low-Mass Stars with DENIS. Preliminary Results on a Star Forming Region: Orion.- Brown Dwarfs in the ISO Central Programme.- IX Conference Summary.- Summary Remarks: Hitting Bottom?.- Author Index.