Kinematic and abundance gradients in the galactic disk

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6458071

Neese, C L

Radial velocities and DDO and BV photometry of 364 G and K stars in the galactic center and anticenter directions were obtained for the purpose of investigating the gradients of abundance and velocity dispersion in the galactic disk. The abundance gradient found for these stars is d(Fe/H)/dR = -0.017 +/- .007 dex/kpc, which is similar to the gradients found in other studies of mixed-age objects. U velocity dispersion is found to depend on both metal abundance and galactocentric distance. For stars observed in the galactic-center direction, the highest velocity dispersion is found in the metal-rich stars, a result which is suggestive of the existence of an old metal-rich population in the inner disk. For the stars observed in the anticenter direction, the dependence is more in accord with the conventional picture of increasing velocity dispersion with time and increasing metal abundance with age. Here, the metal-poor stars are found to have higher velocity dispersion than the normal-abundance stars. Results imply that the relationship between velocity dispersion and age, observe for stars in the neighborhood of the sun, cannot apply unchanged to stars in other parts of the disk.

• Research Organization: Illinois Univ., Urbana (USA)
• OSTI ID: 6458071
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
640105 -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
CORRELATIONS
DISTANCE
GALAXIES
MAIN SEQUENCE STARS
MILKY WAY
PHOTOMETRY
RADIAL VELOCITY
STARS
SUN
VELOCITY