Satellites and Dwarf Galaxies as Probes of Dark Matter

New Mexico State University, Las Cruces NM

Investigators

Abstract

AST-0407072 Klypin This project addresses the so-called crisis in cosmology on small scales, using satellites of isolated galaxies, galaxies in nearby voids, and detailed models of rotation curves. Combining the analysis of observations with theory, methods will be used that complement and expand the traditional approach. A full scale Bayesian probabilistic analysis of satellite galaxy kinematics, using the Sloan Digital Sky Survey data, will probe the (mainly dark matter) mass distribution in the peripheral regions of isolated galaxies. A related part of the crisis, the galaxy content of nearby voids, will be analyzed with shallow samples over a large magnitude range, which will then be compared with cosmological simulations. Finally, the accuracy of the reconstruction of mass profiles from rotation curves must depend on galaxy type, and small variations can significantly mar the mass estimates. Therefore, the present research includes the production of publicly available models of disk galaxies embedded in realistic cosmological dark matter halos. The intent is to raise the quality and reliability of results coming from satellite dynamics, and along the way train two female graduate students and provide catalogs and numerical models to the entire community.