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arXiv · 1711.06377

Planet Candidates from K2 Campaigns 5-8 and Follow-Up Optical Spectroscopy

Erik A. Petigura·Ian J. M. Crossfield·Howard Isaacson·Charles A. Beichman·Jessie L. Christiansen·Courtney D. Dressing·Benjamin J. Fulton·Andrew W. Howard·Molly R. Kosiarek·Sébastien Lépine·Joshua E. Schlieder·Evan Sinukoff·Samuel W. Yee
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Abstract

We present 151 planet candidates orbiting 141 stars from K2 campaigns 5-8 (C5-C8), identified through a systematic search of K2 photometry. In addition, we identify 16 targets as likely eclipsing binaries, based on their light curve morphology. We obtained follow-up optical spectra of 105/141 candidate host stars and 8/16 eclipsing binaries to improve stellar properties and to identify spectroscopic binaries. Importantly, spectroscopy enables measurements of host star radii with $\approx$10% precision, compared to $\approx$40% precision when only broadband photometry is available. The improved stellar radii enable improved planet radii. Our curated catalog of planet candidates provides a starting point for future efforts to confirm and characterize K2 discoveries.

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Erik A. Petigura, Ian J. M. Crossfield, Howard Isaacson, Charles A. Beichman, Jessie L. Christiansen, Courtney D. Dressing, Benjamin J. Fulton, Andrew W. Howard, Molly R. Kosiarek, Sébastien Lépine, Joshua E. Schlieder, Evan Sinukoff, Samuel W. Yee. 2017-11-17. Planet Candidates from K2 Campaigns 5-8 and Follow-Up Optical Spectroscopy. https://doi.org/10.3847/1538-3881%2Faa9b83

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