Near-Infrared Variability in the 2MASS Calibration Fields: A Search for Planetary Transit Candidates

The Two Micron All Sky Survey (2MASS) photometric calibration observations cover ~6 square degrees on the sky in 35 "calibration fields", each sampled in nominal photometric conditions between 562 and 3692 times during the 4 years of the 2MASS mission. We compile a catalog of variables from the calibration observations to search for M dwarfs transited by extrasolar planets. We present our methods for measuring periodic and nonperiodic flux variability. From 7554 sources with apparent K_s magnitudes between 5.6 and 16.1, we identify 247 variables, including extragalactic variables and 23 periodic variables. We have discovered three M dwarf eclipsing systems, including two candidates for transiting extrasolar planets.

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