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arXiv · 1810.08835

A catalog of stars observed simultaneously by Kepler and TESS

Thomas Barclay·Geert Barentsen
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Abstract

The Kepler spacecraft provided the first long-baseline, high-precision photometry for large numbers of stars. This enabled the discovery of thousands of new exoplanets, and the characterization of myriad astrophysical phenomena. However, one of the challenges with interpreting Kepler data has been that no instrument has provided a comparison dataset. Therefore, the replication of Kepler time-series data has remained elusive. The Transiting Exoplanet Survey Satellite (TESS) launched in April 2018 and began science operations in July 2018. During the TESS primary mission, it will survey 85% of the sky. NASA's first two observatories dedicated to discovering exoplanets, Kepler and TESS, were simultaneously operating during 2018. While the Kepler's K2 mission surveyed the ecliptic plane, TESS targets fields outside the ecliptic. However, during September 2018, a small region of the sky was observed simultaneously by both TESS and Kepler as part of TESS's Sector 2 (Aug 22 - Sep 20, 2018) and K2 Campaign 19 (Sep 7 - Sep 26, 2018). The overlap region was 0.5 sq. deg. We identified 171 K2 targets that fell inside TESS Sector 2 field of view, all of which are observed at 30-minute cadence by both missions. The targets range in brightness in the TESS bandpass (Tmag) from 6.7-18.4, with 93 targets brighter than Tmag=15, and 17 brighter than Tmag=12. This dataset provides the first simultaneous, long-duration, high-precision observations of the same targets from different space-based observatories and presents an excellent opportunity to explore instrumental systematics present in the two telescopes.

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Thomas Barclay, Geert Barentsen. 2018-10-20. A catalog of stars observed simultaneously by Kepler and TESS. https://arxiv.org/abs/1810.08835

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