系外行星研究组知识库

We are running a wide field photometric survey under the collaboration between Yunnan Observatories and Hong Kong Astronomical Society with a Centurion 18-inch telescope at the Lijiang station of Yunnan Observatories, China. Its scientific goals are discovering new transiting exoplanetary systems and other types of variable stars, and studying asteroids of the solar system. The survey was designed to monitor several fixed sky areas through time series photometry with short cadences. Since 2016, numerous observing data have been accumulated and reduced by means of dedicated pipelines to deliver the light curves for tens of thousands objects, which are cross-matched through the Carlsberg Meridian Catalog 15 or USNO-B1.0 catalog. Systematic errors and trends that existed in the raw photometric results are simulated through selected reference stars and then removed to improve signal-to-noise ratios of the light curves, which is crucial to detect weak signals like exoplanet transits and other variable stars of low amplitudes in brightness variations. The final data products own the photometric precision better than 0.01 magnitude for stars brighter than 13.8 magnitude in the V band. By means of generalized Lomb-Scargle, phase dispersion minimization, and box-fitting least squares techniques, we have already identified about a thousand of variable stars from the survey, including transiting exoplanet candidates, spotted stars, eclipsing binaries, pulsating stars, and so on. In addition, we have also captured around a thousand of asteroids of the solar system in the survey fields and produced their light curves due to spins.