Color and variability characteristics of point sources in the Faint Sky Variability Survey

We present an analysis of the color and variability characteristics for point sources in the Faint Sky Variability Survey (FSVS). The FSVS cataloged similar to 23 deg(2) in BVI filters from similar to 16 to 24 mag to investigate variability in faint sources at moderate-to-high Galactic latitudes. Point-source completeness is found to be > 83% for a selected representative sample (V = 17.5 - 22.0 mag, B - V = 0.0 - 1: 5) containing both photometric B, V detections and 80% of the time-sampled V data available compared to a basic internal source completeness of 99%. Multiepoch ( 10 - 30) observations in V spanning minutes to years modeled by light-curve simulations reveal amplitude sensitivities to similar to 0.015 - 0.075 mag over a representative V = 18 - 22 mag range. Periodicity determinations appear viable to time-scales of order 1 day or less using the most sampled fields ( similar to 30 epochs). The fraction of point sources is found to be generally variable at 5% - 8% over V = 17.5 - 22.0 mag. For V brighter than 19 mag, the variable population is dominated by low- amplitude (< 0.05 mag) and blue (B - V < 0.35) sources, possibly representing a population of gamma Doradus stars. Overall, the dominant population of variable sources are bluer than B - V 0: 65 and have main-sequence colors, likely reflecting larger populations of RR Lyrae, SX Phe, gamma Doradus, and W UMa variables.