Changes from Version 1 of Talks/Fall2009/SpecialSeminars/091203

Show
Ignore:
Author:
kvj@astro.columbia.edu (IP: 67.81.68.56)
Timestamp:
10/27/09 05:11:39 (10 years ago)
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • Talks/Fall2009/SpecialSeminars/091203

    v0 v1  
     1Dr David R Law (UCLA) 
     2 
     3"Kiloparsec-Scale Kinematics in High-Redshift Star-Forming Galaxies" 
     4 
     5I discuss the results of a multi-year Keck/LGSAO survey of the internal kinematics of rapidly star-forming galaxies at redshift z ~ 2 - 3 as traced by nebular line emission on angular scales ~ 0.1 arcsec.  At most 5 of the 13 best-detected galaxies have spatially resolved velocity gradients consistent with rotation, while the remaining galaxies have relatively featureless or irregular velocity fields.  All of our galaxies exhibit high local velocity dispersions ~ 60 - 100 km/s, suggesting that even for those galaxies with clear velocity gradients rotation about a preferred kinematic axis may not be the dominant means of physical support.  The dynamical importance of cold gas appears to be the primary factor governing the observed kinematics, and I discuss possible mechanisms for the accretion of low angular-momentum gas and the early formation of quasi-spheroidal systems. 
     6