MagLiteS Carina II and Carina III spectroscopy Virtual Observatory Resource

Authors
  1. Li T.S.
  2. Simon J.D.
  3. Pace A.B.
  4. Torrealba G.
  5. Kuehn K.
  6. Drlica-Wagner A.,Bechtol K.
  7. Vivas A.K.
  8. van der Marel R.P.
  9. Wood M.
  10. Yanny B.
  11. Belokurov V.,Jethwa P.
  12. Zucker D.B.
  13. Lewis G.
  14. Kron R.
  15. Nidever D.L.
  16. Sanchez-Conde M.A.,Ji A.P.
  17. Conn B.C.
  18. James D.J.
  19. Martin N.F.
  20. Martinez-Delgado D.,Noel N.E.D.
  21. Published by
    CDS
Abstract

We present Magellan/IMACS, Anglo-Australian Telescope/AAOmega+2dF, and Very Large Telescope/GIRAFFE+FLAMES spectroscopy of the Carina II (CarII) and Carina III (CarIII) dwarf galaxy candidates, recently discovered in the Magellanic Satellites Survey (MagLiteS). We identify 18 member stars in Car II, including two binaries with variable radial velocities and two RR Lyrae stars. The other 14 members have a mean heliocentric velocity v_hel_=477.2+/-1.2km/s and a velocity dispersion of {sigma}_v_=3.4_-0.8_^+1.2^km/s. Assuming Car II is in dynamical equilibrium, we derive a total mass within the half-light radius of 1.0_-0.4_^+0.8^x10^6^M_{sun}_, indicating a mass-to-light ratio of 369_-161_^+309^M_{sun}_/L_{sun}_. From equivalent width measurements of the calcium triplet lines of nine red giant branch (RGB) stars, we derive a mean metallicity of [Fe/H]=-2.44+/-0.09 with dispersion {sigma}_[Fe/H]_=0.22_-0.07_^+0.10^. Considering both the kinematic and chemical properties, we conclude that CarII is a dark-matter-dominated dwarf galaxy. For CarIII, we identify four member stars, from which we calculate a systemic velocity of v_hel_=284.6_-3.1_^+3.4^km/s. The brightest RGB member of CarIII has a metallicity of [Fe/H]=-1.97+/-0.12. Due to the small size of the Car III spectroscopic sample, we cannot conclusively determine its nature. Although these two systems have the smallest known physical separation ({Delta}d~10kpc) among Local Group satellites, the large difference in their systemic velocities, ~200km/s, indicates that they are unlikely to be a bound pair. One or both systems are likely associated with the Large Magellanic Cloud (LMC), and may remain LMC satellites today. No statistically significant excess of {gamma}-ray emission is found at the locations of Car II and Car III in eight years of Fermi-LAT data.

Keywords
  1. galaxies
  2. spectroscopy
  3. radial-velocity
  4. metallicity
  5. line-intensities
  6. infrared-photometry
  7. visible-astronomy
  8. Wide-band photometry
Bibliographic source Bibcode
2018ApJ...857..145L
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/857/145
IVOA Identifier IVOID
ivo://CDS.VizieR/J/ApJ/857/145
Document Object Identifer DOI
doi:10.26093/cds/vizier.18570145

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/857/145
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/857/145
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/857/145
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/ApJ/857/145/table2?
https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/857/145/table2?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/857/145/table2?
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/857/145/table4?
https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/857/145/table4?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/857/145/table4?

History

2019-04-25T13:47:13Z
Resource record created
2019-04-25T13:47:13Z
Created
2021-07-08T14:28:49Z
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