[P-AE16] 系外惑星

[PAE16-09] New Validated Planets in Overlapping K2 Campaigns

*Jerome Pitogo de Leon¹、John Livingston¹、Michael Endl⁴、William Cochran^5,4、Teruyuki Hirano¹⁸、Masayuki Kuzuhara^15,14、Rafael Garcia¹¹、Savita Mathur^6,7、Fei Dai^10,9、Alessandro Trani²、Judith Korth^6,7、Kristine Lam⁸、Enrique Diez Alonzo¹⁷、Amadeo Castro Gonzalez¹⁷、Malcolm Fridlund^12,13、Akihiko Fukui³、Rafa Luque^6,7、Norio Narita^16,2,15,14、Enric Palle^6,7、Motohide Tamura^1,14,15、KESPRINT team (1.Department of Astronomy, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan、2.Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan、3.Department of Earth and Planetary Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ky, Tokyo 113-0033, Japan、4.Department of Astronomy and McDonald Observatory, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712, USA、5.Center for Planetary Systems Habitability, The University of Texas at Austin, Austin TX USA、6.Instituto de Astrofisica de Canarias (IAC), 38205 La Laguna, Tenerife, Spain、7.Departamento de Astrofisica, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain、8.Center for Astronomy and Astrophysics, Technical University Berlin, Hardenbergstr. 36, 10623 Berlin, Germany、9.Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Blvd, Pasadena CA 91125、10.Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA、11.AIM, CEA, CNRS, Universite Paris-Saclay, Universite Paris Diderot, Sorbonne Paris Cité, F-91191 Gif-sur-Yvette, France、12.Leiden Observatory, Leiden University, 2333CA Leiden, The Netherlands、13.Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, SE-439 92 Onsala, Sweden、14.Astrobiology Center, NINS, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan、15.National Astronomical Observatory of Japan, NINS, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan、16.JST, PRESTO, 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan 、17.Instituto Universitario de Ciencias y Tecnologias Espaciales de Asturias (ICTEA), C.Independencia 13, E-33004 Oviedo, Spain、18.Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan)

キーワード：exoplanet, transit, imaging

We analysed 72 candidate planetary systems first identified during Campaigns 5 and 6 (C5 and C6) of the NASA K2 Mission. We set out to validate these systems using a suite of follow-up observations including adaptive optics, speckle imaging, and reconnaissance spectroscopy. The overlap between C5 with C16 and C18, and C6 with C17, yields light curves with longer baselines that allow us to measure the transit ephemeris very precisely, revisit single transit candidates identified in earlier campaigns, and search for additional transiting planets with longer periods not detected in previous works. Using vespa, we compute false positive probabilities less than 1% for 35 candidates and hence statistically validate them as planets. These planets have a typical size of 2.2R⊕ and orbital periods between 1.99 and 52.71 days. We highlight interesting systems including a sub-Neptune with the longest period with more than two transits detected from K2, sub-Saturns around F stars, and several multi-planetary systems in a variety of architectures, four of which are new discoveries. These results show that a wealth of planetary systems still remain in the K2 data, many ofwhich can be validated using minimal follow-up observations and taking advantage of analyses presented in previous catalogs.