SEARCHES FOR VARIABILITY IN THE MILKY WAY BULGE WITH THE VVV SURVEY

VVV is an ongoing near-IR, multi-band, time-series survey of the Galactic bulge and plane. Here we summarize the first results from a search for variability in selected fields of the VVV bulge area. The VISTA Variables in the Via Lactea (VVV) is an ESO public near-IR variability survey scanning the Milky Way bulge and southern Galactic disk (Minniti et al. 2010; Saito et al. 2012). VVV is producing a ZY JHKs catalogue of about a billion sources over an area of 562 square degrees and upon completion will deliver Ks-band light-curves for a few million variable sources with 80-100 data-point covering many years (Catelan et al. 2013). Data taken during 2010-2012 covered the whole VVV bulge area in the five passbands, plus up to 30−40 Ks-band epochs with a large baseline. From a total of 42 selected bulge tiles covering ∼68 sq deg in both inner (b 8 deg) part of the bulge we produced ∼53 million light-curves with 16-40 data points per object. This data set allow us to start the search for variability in the Galactic bulge using different strategies. Figure 1 shows illustrative light-curves which summarize the first results from this search, from the study of tiny variations due to planetary transits in the outermost region of the VVV bulge area, to the discovery of hundreds of long period variables, and detection of microlensing events and explosive Nova eruptions in the Galactic center.