[Previous] | [Session 129] | [Next]
S.S. McGaugh (U. Maryland), J.M. Schombert, G.D. Bothun (U. Oregon), W.J.G. de Blok (ATNF)
We extend the Tully-Fisher relation over five decades in stellar mass using new data for dwarf low surface brightness galaxies. The data include many faint galaxies with masses as low as M* = 106 M\sun and circular velocities as low as Vc = 40 km/s. We find a clear break in the optical-NIR Tully-Fisher relation: galaxies with Vc < 90 km/s fall systematically below the relation defined by brighter galaxies. These faint galaxies are however very gas rich; adding in the gas mass and plotting baryonic mass Mb = M* + Mgas in place of luminosity restores a single linear relation. The Tully-Fisher relation appears fundamentally to be a relation between rotation velocity and total baryonic mass.
This work has been supported in part by NSF grants AST 84-08225, AST 87-18465, AST 99-01663 and NASA grants NGL 05002140 and NAGW 1710.
If you would like more information about this abstract, please follow the link to http://www.astro.umd.edu/~ssm. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.
The author(s) of this abstract have provided an email address for comments about the abstract: ssm@astro.umd.edu