Geos Rr Lyrae Database And Survey: A Professional-Amateur Project

GEOS, a European professional-amateur association, has collected in a database available times of maximum of RR Lyrae stars. We scanned the publications back to more than one century for this purpose. Recent observations are regularly added to the database. Measurements from amateur astronomer groups (GEOS, BAV, AAVSO) and from the robotic telescopes TAROT are used. To date, the database contains about 96 000 maximum times from 4 000 RR Lyrae stars. This database is particularly useful to study period variations of RR Lyrae stars including phenomena like the Blazhko effect and light travel time effects in binaries.