Radial velocities of stars in Bootes I Virtual Observatory Resource

Authors
  1. Koposov S.E.
  2. Gilmore G.
  3. Walker M.G.
  4. Belokurov V.
  5. Evans N.W.,Fellhauer M.
  6. Gieren W.
  7. Geisler D.
  8. Monaco L.
  9. Norris J.E.
  10. Okamoto S.,Penarrubia J.
  11. Wilkinson M.
  12. Wyse R.F.G.
  13. Zucker D.B.
  14. Published by
    CDS
Abstract

We develop, implement, and characterize an enhanced data reduction approach which delivers precise, accurate, radial velocities from moderate resolution spectroscopy with the fiber-fed VLT/FLAMES+GIRAFFE facility. This facility, with appropriate care, delivers radial velocities adequate to resolve the intrinsic velocity dispersions of the very faint dwarf spheroidal (dSph) galaxies. Importantly, repeated measurements let us reliably calibrate our individual velocity errors (0.2km/s<={delta}_V_<=5km/s) and directly detect stars with variable radial velocities. We show, by application to the Bootes I dSph, that the intrinsic velocity dispersion of this system is significantly below 6.5km/s reported by previous studies. Our data favor a two-population model of Bootes I, consisting of a majority "cold" stellar component, with velocity dispersion 2.4^+0.9^_-0.5_km/s, and a minority "hot" stellar component, with velocity dispersion ~9km/s, although we cannot completely rule out a single component distribution with velocity dispersion 4.6^0.8^_-0.6_km/s. We speculate that this complex velocity distribution actually reflects the distribution of velocity anisotropy in Bootes I, which is a measure of its formation processes.

Keywords
  1. galaxies
  2. radial-velocity
  3. visible-astronomy
  4. sloan-photometry
  5. metallicity
Bibliographic source Bibcode
2011ApJ...736..146K
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/736/146
IVOA Identifier IVOID
ivo://CDS.VizieR/J/ApJ/736/146
Document Object Identifer DOI
doi:10.26093/cds/vizier.17360146

Access

IVOA Table Access TAP
https://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).
https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/736/146/table1?
https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/736/146/table1?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/736/146/table1?

History

2013-02-04T08:02:44Z
Resource record created
2013-02-04T08:02:44Z
Created
2018-01-05T08:55:58Z
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