The Andromeda Dwarf Spheroidal Galaxies

Dwarf Spheroidal Galaxies

Internal Kinematics of the Andromeda Ii Dwarf Spheroidal Galaxy

The High Resolution Echelle Spectrometer on the Keck I telescope has been used to measure nine radial velocities having a median precision of ' 2 km s−1 for seven red giants belonging to the isolated dwarf spheroidal galaxy Andromeda II (And II). We find a weighted mean radial velocity of vr = –188±3 km s−1 and a central velocity dispersion of σ0 = 9.3 −2.6 km s −1. There may be evidence for a ...

Dwarf Spheroidal Galaxies in the Virgo Cluster

We present a study of the smallest and faintest galaxies found in a very deep photographic R band survey of regions of the Virgo Cluster, totalling over 3 square degrees, made with the UK Schmidt Telescope. The objects we detect have the same physical sizes and surface brightnesses as Local Group dwarf spheroidal galaxies. The luminosity function of these extremely low luminosity galaxies (down...

The Kinematics of Dwarf Spheroidal Galaxies

I review observational data on the kinematic properties of dwarf spheroidal galaxies in the halo of the Milky Way and beyond. The present data confirm previous claims that these small galaxies have unusually large central velocity dispersions. ‘Simple’ sources of bias such as binary stars, internal atmospheric motions, measurement errors and small sample sizes cannot explain the large dispersio...

The Internal Kinematics of Dwarf Spheroidal Galaxies

The status of kinematic observations in Local Group dwarf spheroidal galaxies (dSphs) is reviewed. Various approaches to the dynamical modelling of these data are discussed and some general features of dSph dark matter haloes based on simple mass models are presented.