A High-Performance, Catalog-Driven Approach to Light Curve Extraction for Wide-Field Photometric Surveys

Abstract

The Kilodegree Extremely Little Telescope (KELT) is an ongoing, wide-field, all-sky, time-domain photometric survey built to discover new transiting extrasolar planets of high scientific value orbiting bright host stars. Several science results from the survey are discussed. The surprising discovery of a massive brown dwarf (KELT-1b) in a short-period orbit around a rapidly rotating F-type host star provided one of the few high-precision brown dwarf mass and radius measurements to date and identified an unlikely environment where such objects may be found. A bright, recent supernova (SN2014J) was serendipitously observed by KELT producing a high-precision, high-cadence light curve. Production and analysis of these data allowed the setting of novel and useful limits on the supernova progenitor and its environmental interaction. The recent discovery of KELT-19Ab, a transiting exoplanet in retrograde orbit around a bright, early-type host star is likely the first such specimen discovered with a metal-enhanced (Am-type) host star. The presence of a distant stellar companion complicated the follow-up process by mimicking a common astrophysical false positive and thus provides an important lesson in the importance of thorough candidate vetting. Following the discussion of past science results, a new suite of tools and methods termed Catalog-Driven Extraction (CDE) is introduced. CDE comprises a set of significant improvements and changes to existing survey methods that deliver improved data quality for a significantly expanded set of celestial objects (over 14 million) compared to the existing KELT data set. Data processing methods, the resultant data products, and the impact of simplified data sharing are described in detail.