Collaborative Research: Completion of the Southern Proper Motion Program

Michigan State University, East Lansing MI

Investigators

Abstract

AST 0098508 Beers In a collaborative research project, Dr. William Van Altena, of Yale Southern Observatory, and Dr. Timothy Beers, of Michigan State University, will use the newly installed CCD cameras at the Yale Southern Observatory in Argentina in order to complete the Yale/San-Juan Southern Proper Motion (SPM) program. The first two catalogs of the SPM have already demonstrated the high quality of the absolute proper motions that are attainable within this program. The CCD system will allow completion of the 2nd-epoch observations of the southern sky and, furthermore, will provide the first full southern-sky set of photometry in V and B, down to a magnitude limit of V = 18.0 and B = 19.0. While the first two SPM Catalogs were based on input lists of interesting objects as well as randomly selected stars for kinematic studies, the new CCD camera system, and recent completion of the digitization of all SPM plates by the Precision Measuring Machine of the U.S. Naval Observatory, will allow the new version of the SPM Catalog to be complete to the limiting magnitude of the 1st-epoch plates. The science return from this effort will be enormous! During this award period, about 6000 square degrees, or three-quarters of the remaining SPM fields should be observed and analyzed. The immediate motivation for the project is linked to exploration of the kinematics and dynamics of the Galaxy, using not only randomly selected anonymous stars but also subsets of special interest; primarily the recently completed lists of tens of thousands of metal-poor (MP) and field horizontal- branch/main-sequence A-type (FRB/A) candidate stars obtained from digital scans of the HK survey plates of Beers and colleagues, and the even larger set of interesting targets generated from the stellar component of the Ramburg/ESO Survey. These two surveys form the basis for present spectroscopic exploration of the nature of the early Galaxy and its chemical and dynamical evolution, and hence are of immediate interest. This information will be combined with radial velocities already in hand, or to be obtained from planned large-scale spectroscopic follow-up, in order to determine full space motions for the most interesting targets from the other surveys long before proper motions and distance measurements are obtained with the space missions FAME and SIM. ***