Accession Number : ADA294138

Title :   RR Lyrae Variable Stars In The CCD/Transit Instrument Survey.

Descriptive Note : Doctoral thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Wetterer, Charles J.

PDF Url : ADA294138

Report Date : JUL 1995

Pagination or Media Count : 375

Abstract : RR Lyrae variable stars have long been recognized as important tools in probing the mass, chemical distribution and kinematics of the Galaxy from the inner recesses of the nuclear bulge to the outer environs of the distant Galactic halo. This dissertation chronicles an RR Lyrae variable star survey from a thorough description of the initial observations with the CCD/Transit Instrument (CTI), to an examination of RR Lyrae space density and the Galactic mass using the discovered RR Lyrae stars. The RR Lyrae space density as a function f Galactocentric distance is shown to be a power-law function (R-3 to -3.5) and consistent with an ellipsoidal distribution in the nuclear bulge and more spherically symmetric distribution in the Galactic halo. The unique area of the CTI survey and comparison to other RR Lyrae surveys verifies this function is valid throughout the Galactic halo and over the range of Galactocentric distances sampled (0.6 < R < 40 kpc). Local underdensities and overdensities of RR Lyrae stars are discussed, including a possible resonance with the Magallenic Clouds (R 50 kpc).

Descriptors :   *VARIABLE STARS, KINEMATICS, SURVEYS, SYMMETRY, SPECTROMETERS, CHARGE COUPLED DEVICES, GALAXIES.

Subject Categories : Astronomy

Distribution Statement : APPROVED FOR PUBLIC RELEASE