Chemical Tagging of Solar Neighborhood Kinematic Streams

Public Deposited
Analytics

Downloadable Content

Download PDF
Request Version for Screen Reader
Last Modified
  • March 20, 2019
Creator
  • Stringer, Christopher Bayard
    • Affiliation: College of Arts and Sciences, Department of Physics and Astronomy
Abstract
  • Elemental abundance measurements for lanthanum, europium, and iron are presented for 504 stars in the solar neighborhood. The bulk of the data are planet search spectra taken with HIRES on the Keck I telescope at R=50,000, but a subset of 45 kinematically selected stars were observed on the Harlan J. Smith Telescope at McDonald Observatory at R=60,000 and S/N=100 at the 3988 angstrom lanthanum line and S/N=250 around 5240 angstrom near the iron lines. Statistical analyses of stellar kinematics in the solar neighborhood reveal much kinematic substructure in the disk, though it is not readily apparent whether this substructure is extragalactic or dynamical in origin. Much of the substructure can be quickly identified as well known moving groups of stars such as the Hercules, Sirius, and Hyades stellar streams. Additionally, the subset of kinematically selected stars observed at McDonald Observatory are members of a stellar stream putatively identified by Amina Helmi as part of a merger remnant. Taking advantage of a large data set and a homogeneous spectral analysis, a Kolmogorov-Smirnov hypothesis test is applied to investigate the possibility that these kinematic structures are chemically distinct from the Galactic Disk. In all cases, the kinematic streams have chemistries roughly consistent with the Galactic disk trends, although the statistical analyses suggest some subtle variations. The accretion hypothesis is not completely ruled out for Helmi's stream, but the chemical variations are interpreted primarily in terms of dynamical effects.
Date of publication
DOI
Resource type
Rights statement
  • In Copyright
Note
  • "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Physics & Astronomy."
Advisor
  • Carney, Bruce
Language
Publisher
Place of publication
  • Chapel Hill, NC
Access right
  • Open access
Date uploaded
  • March 18, 2013

Relations

Parents:

This work has no parents.

Items

Thumbnail Title Date Uploaded Visibility Actions
file details Chemical tagging of solar neighborhood kinematic streams 2019-04-10 Public Download