NOAO > Observing Info > Approved Programs > 2013A-0321
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NOAO > Observing Info > Approved Programs > 2013A-0321 |
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PI: Alessandro Sonnenfeld, UC Santa Barbara, sonnen@physics.ucsb.edu
Address: Department of Physics, Broida Hall, Building 572, Santa Barbara, CA, 93106-9530, USA
CoI: Tommaso Treu, UC Santa Barbara
CoI: Sherry Suyu, UC Santa Barbara
CoI: Raphael Gavazzi, Institut Astrophysique de Paris
CoI: Phil Marshall, University of Oxford
Title: The mass assembly of early-type galaxies with SL2S
Abstract:
How do massive early-type galaxies form? Merging is thought to be a key
process, but the details are not clear: the important merger events could be
minor or major, wet or dry. A key test for any theory of massive galaxy
evolution is to explain the observed total density profiles of early-type
galaxies, which can be precisely measured by joint analysis of strong
gravitational lensing and stellar kinematics data. We are constructing a
sample of 35 lenses at redshift 0.4--0.7, detected in the CFHTLS imaging
survey, to investigate our tentative detection of an average steepening of
the density profiles with cosmic time. To model each galaxy's profile slope
accurately we need an accurate measurement of the lensed source redshift,
which for some systems is best made in the NIR wavebands. With its broad
wavelength coverage, GNIRS is very well-suited to this work: we propose to
measure 5 source redshifts in this way in semester 2013A, to complete our
observational campaign.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360
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NOAO > Observing Info > Approved Programs > 2013A-0321 |
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