Bayesian analysis of resolved stellar spectra Virtual Observatory Resource

Authors
  1. Walker M.G.
  2. Olszewski E.W.
  3. Mateo M.
  4. Published by
    CDS
Abstract

We introduce a Bayesian method for fitting faint, resolved stellar spectra in order to obtain simultaneous estimates of redshift and stellar-atmospheric parameters. We apply the method to thousands of spectra - covering 5160-5280{AA} at resolution R~20000 - that we have acquired with the MMT/Hectochelle fibre spectrograph for red giant and horizontal branch candidates along the line of sight to the Milky Way's dwarf spheroidal satellite in Draco. The observed stars subtend an area of ~4deg^2^, extending ~3 times beyond Draco's nominal 'tidal' radius. For each spectrum, we tabulate the first four moments - central value, variance, skewness and kurtosis - of posterior probability distribution functions representing estimates of the following physical parameters: line-of-sight velocity (v_los_), effective temperature (T_eff_), surface gravity (logg) and metallicity ([Fe/H]). After rejecting low-quality measurements, we retain a new sample consisting of 2813 independent observations of 1565 unique stars, including 1879 observations for 631 stars with (as many as 13) repeat observations. Parameter estimates have median random errors of v_los_=0.88km/s, T_eff_=162K, {sigma}logg=0.37dex and {sigma}[Fe/H]=0.20dex. Our estimates of physical parameters distinguish ~470 likely Draco members from interlopers in the Galactic foreground.

Keywords
  1. galaxies
  2. giant-stars
  3. horizontal-branch-stars
  4. spectroscopy
  5. visible-astronomy
  6. sloan-photometry
Bibliographic source Bibcode
2015MNRAS.448.2717W
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/448/2717
IVOA Identifier IVOID
ivo://CDS.VizieR/J/MNRAS/448/2717
Document Object Identifer DOI
doi:10.26093/cds/vizier.74482717

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/448/2717
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/448/2717
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/448/2717
IVOA Table Access TAP
http://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/448/2717/table4?
https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/448/2717/table4?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/448/2717/table4?
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/448/2717/table5?
https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/448/2717/table5?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/448/2717/table5?

History

2016-03-09T10:54:31Z
Resource record created
2016-03-09T10:54:31Z
Created
2024-08-14T20:20:19Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr