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I have moved to UCLA and am no longer updating this page.
The new equivalent can be found at http://www.astro.ucla.edu/~drlaw/research.html.
Major Current Research Projects
High-Redshift Galaxy Structure:
In collaboration with Dr. Chuck Steidel (Caltech) I am studying the spatially resolved properties of galaxies in the redshift range z ~ 2 - 3 in an effort to constrain their dynamical properties, evolution, and relation to the intergalactic environment. The bulk of this work at present focuses on using integral-field spectroscopy with laser-guided adaptive optics to probe kinematics at the Keck diffraction limit using the OSIRIS spectrograph. These spatially resolved kinematics are coupled with detailed analyses of the morphological properties revealed by deep HST/ACS optical morphologies (see our GOODS-N database) and an upcoming program of near-IR imaging using HST/WFC3. By relating these data to stellar population models from broadband photometry and large-scale gaseous outflows traced by UV spectroscopy we aim to understand the mechanisms by which these galaxies accreted their gas and process it into luminous stellar structures.
Similarly, we have recently begun a program to use the spatial resolution of OSIRIS to suppress emission from the central AGN of high redshift QSOs in order to derive the star formation properties of their host galaxies and relate the AGN phase to the global picture of galaxy evolution.
Galactic Structure and Dynamics
I am also involved in projects to map the development of structure in the Milky Way Galaxy with particular regard to the formation and evolution of tidal streams from Local Group dwarf spheroidals. The most active current project concerns the chemical and orbital history of the Sagittarius dwarf in collaboration primarily with Drs. Steve Majewski (UVA) and Kathryn Johnston (Columbia). Click here to see a movie (~ 10 MB) of how we think the Milky Way and some of its tidal streams appear.
See also our web resource for the discoveries
recently presented by our group.
One major project in this area has been developing N-body simulation models of the tidal disruption of the Sagittarius (Sgr) dwarf spheroidal galaxy (this project began as my undergraduate thesis). By constraining these models to fit observational data from 2MASS, we have gained a greater understanding of the gravitational potential of the Milky Way Galaxy, and of the possible shape of its cold dark matter halo. Papers from this work have been published in the Astrophysical Journal- see also our web resource for the discoveries recently presented by our group. While the gross orbital features of the Sgr stream have now been well mapped, modeling the chemical evolution of the stars within this stream and the corresponding star formation history of the pre-disruption satellite remains an open challenge.
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