Title: The Virgo Overdensity as seen by RR Lyrae stars

Abstract:
The Virgo Overdensity (VOD) is a vast overdensity of stars in the halo between 5 and 20 kpc, 
spanning a few thousand square degrees of the sky (as seen by SDSS). It has been interpreted 
as a merger event although several kinematic sub-structures have been found in the region 
suggesting a more complex merger history. In the last couple of years several major surveys of 
RR Lyrae stars have become publicly available allowing a more extensive investigation of the 
region. Being standard candles, these stars allow to dissentangle streams in the region by their 
distance and velocity. We combined data from La Silla-QUEST, the Catalina Sky Surveys and 
LINEAR, with SDSS spectroscopy and our own observations to study the kinematic groups in 
the region. Besides the already known features in the region, we found yet another 
kinematic sub-structure in the halo beyond 25 kpc.