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arXiv · 1711.03608

Variability Properties of 4 Million Sources in the $TESS$ Input Catalog Observed with the Kilodegree Extremely Little Telescope Survey

Ryan J. Oelkers·Joseph E. Rodriguez·Keivan G. Stassun·Joshua Pepper·Garrett Somers·Stella Kafka·Daniel J. Stevens·Thomas G. Beatty·Robert J. Siverd·Michael B. Lund·Rudolf B. Kuhn·David James·B. Scott Gaudi
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Abstract

The Kilodegree Extremely Little Telescope (KELT) has been surveying more than $70\%$ of the celestial sphere for nearly a decade. While the primary science goal of the survey is the discovery of transiting, large-radii planets around bright host stars, the survey has collected more than $10^6$ images, with a typical cadence between $10-30$ minutes, for more than $4$ million sources with apparent visual magnitudes in the approximate range $7<V<13$. Here we provide a catalog of 52,741 objects showing significant large-amplitude fluctuations likely caused by stellar variability and 62,229 objects identified with likely stellar rotation periods. The detected variability ranges in $rms$-amplitude from 3 mmag to 2.3 mag, and the detected periods range from $\sim$0.1 days to $\gtrsim$2000 days. We provide variability upper limits for all other $\sim$4 million sources. These upper limits are principally a function of stellar brightness, but we achieve typical 1$\sigma$ sensitivity on 30-minute timescales down to $\sim5$ mmag at $V\sim 8$, and down to $\sim43$ mmag at $V\sim 13$. We have matched our catalog to the $TESS$ Input catalog and the AAVSO Variable Star Index to precipitate the follow up and classification of each source. The catalog is maintained as a living database on the Filtergraph visualization portal at the URL https://filtergraph.com/kelt$\_$vars

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Ryan J. Oelkers, Joseph E. Rodriguez, Keivan G. Stassun, Joshua Pepper, Garrett Somers, Stella Kafka, Daniel J. Stevens, Thomas G. Beatty, Robert J. Siverd, Michael B. Lund, Rudolf B. Kuhn, David James, B. Scott Gaudi. 2017-11-09. Variability Properties of 4 Million Sources in the $TESS$ Input Catalog Observed with the Kilodegree Extremely Little Telescope Survey. https://doi.org/10.3847/1538-3881%2Faa9bf4

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