On kinematic substructure in the Sextans dwarf spheroidal galaxy

Matthew G. Walker, Mario Mateo, Edward W Olszewski, Jayanta Kumar Pal, Bodhisattva Sen, Michael Woodroofe

Research output: Contribution to journalArticle

57 Citations (Scopus)

Abstract

We present multifiber echelle radial velocity results for 551 stars in the Sextans dwarf spheroidal galaxy and identify 294 stars as probable Sextans members. The projected velocity dispersion profile of the binned data remains flat to a maximum angular radius of 30′. We introduce a nonparametric technique for estimating the projected velocity dispersion surface and use this to search for kinematic substructure. Our data do not confirm previous reports of a kinematically distinct stellar population at the Sextans center. Instead we detect a region near the Sextans core radius that is kinematically colder than the overall Sextans sample with 95% confidence.

Original languageEnglish (US)
JournalAstrophysical Journal
Volume642
Issue number1 II
DOIs
StatePublished - May 1 2006

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dwarf galaxies
substructures
kinematics
stars
radii
radial velocity
confidence
estimating
profiles

Keywords

  • Galaxies: dwarf
  • Galaxies: individual (Sextans)
  • Galaxies: kinematics and dynamics
  • Local Group

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

On kinematic substructure in the Sextans dwarf spheroidal galaxy. / Walker, Matthew G.; Mateo, Mario; Olszewski, Edward W; Pal, Jayanta Kumar; Sen, Bodhisattva; Woodroofe, Michael.

In: Astrophysical Journal, Vol. 642, No. 1 II, 01.05.2006.

Research output: Contribution to journalArticle

Walker, Matthew G. ; Mateo, Mario ; Olszewski, Edward W ; Pal, Jayanta Kumar ; Sen, Bodhisattva ; Woodroofe, Michael. / On kinematic substructure in the Sextans dwarf spheroidal galaxy. In: Astrophysical Journal. 2006 ; Vol. 642, No. 1 II.
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