No WIMP mini-spikes in dwarf spheroidal galaxies

Dwarf Spheroidal Galaxies

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...

Dark matter distribution in dwarf spheroidal galaxies

We present predictions for the line-of-sight velocity dispersion profiles of dwarf spheroidal galaxies and compare them to observations in the case of the Fornax and Draco dwarfs. The predictions are made in the framework of standard dynamical theory of two-component (stars and dark matter) spherical systems with different velocity distributions. The stars are assumed to be distributed accordin...

Blue straggler stars in dwarf spheroidal galaxies

Blue straggler star (BSS) candidates have been observed in all old dwarf spheroidal galaxies (dSphs), however whether or not they are authentic BSSs or young stars has been a point of debate. To both address this issue and obtain a better understanding of the formation of BSSs in different environments we have analysed a sample of BSS candidates in two nearby Galactic dSphs, Draco and Ursa Mino...

Search for HI in Dwarf Spheroidal Galaxies

After reviewing the HI content and distribution in extreme dwarf irregular (dIrr) and dwarf elliptical (dE) galaxies, previous searches for HI in dwarf spheroidal (dSph) galaxies will be discussed. I will report on the recent detections of HI probably associated with the Local Group (LG) dSph Sculptor and dIrr/dSph Phoenix, obtained with the ATCA, along with a similar detection in the Centaurus...