NOAO >   Observing Info >   Approved Programs >   2009A-0126

Small NOAO Logo

Proposal Information for 2009A-0126


PI: Karun Thanjavur, University of Victoria, karun@uvic.ca
Address: Department of Physics and Astronomy, PO Box 3055, Victoria, BC, V8W 3P6, Canada

CoI: Mark Swinbank, University of Durham
CoI: Philip Marshall, UC Santa Barbara
CoI: Jean-Paul Kneib, Laboratoire d'Astrophysique de Marseille
CoI: David Crampton, Herzberg Institute of Astrophysics
CoI: Jon Willis, University of Victoria
CoI: Members of SL2S Collaboration, Observatoire Midi-Pyrenees

Title: The relative distribution of visible and dark matter in galaxy groups selected by gravitational lensing

Abstract: We aim to understand non-linear structure formation within the Lambda-CDM framework by characterizing the mass distributions and mass/light ratios of galaxy groups. These structures represent the critical break observed between cluster and field galaxy mass scales. We use strong gravitational lensing and dynamical mass measurements to probe, without significant bias, the mass distribution up to the virial radius. With our 2007A GMOS/MOS proposal, we successfully determined the velocity dispersions of 2 lensing groups from 15 candidates discovered in the CFHTLS-Wide fields with our automated search method. For the 3 high-quality groups in this proposal, HST Cycle16 imaging is already in hand. Confirmation of group membership, velocity dispersions and lensed arc redshifts from this GMOS/MOS proposal are crucial for modeling the lenses and thus determining their mass distribution. Our mass estimate will be extended beyond the virial radius by weak lensing and X-ray observations undertaken by our Strong Lensing Legacy Survey (SL2S) collaborators.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2009A-0126

noaoprop-help@noao.edu

Small NOAO Logo