RR Lyrae stars in the Bootes structureDall'Ora M., Clementini G., Kinemuchi K., Ripepi V., Di Fabrizio L., Di Criscienzo M., Kuehn C., Marconi M., Smith H.A.
BVI time-series photometry of the new Milky Way satellite recently discovered in the Bootes constellation (Belokurov et al. 2006, astro-ph/0604355) was collected at the TNG, WIRO and Loiano telescopes and used to search for variable stars. We have identified a non-negligible population of RR Lyrae variables, which confirm the presence of an old population in the newly discovered structure. The analysis of the period distribution, coupled with evolutionary informations from the multi-band color-magnitude diagrams, provides important hints on the nature and history of this intriguing object.