The Kepler-454 system : A small, not-rocky inner planet, a Jovian world, and a distant companion
View/ Open
Date
14/01/2016Author
Funder
Grant ID
ST/M001296/1
ST/I000666/1
PP/D000890/1
ST/J001651/1
ST/G001006/1
PP/F000065/1
Keywords
Metadata
Show full item recordAbstract
Kepler-454 (KOI-273) is a relatively bright (V = 11.69 mag), Sun-like starthat hosts a transiting planet candidate in a 10.6 d orbit. From spectroscopy, we estimate the stellar temperature to be 5687 +/- 50 K, its metallicity to be [m/H] = 0.32 +/- 0.08, and the projected rotational velocity to be v sin i <2.4 km s-1. We combine these values with a study of the asteroseismic frequencies from short cadence Kepler data to estimate the stellar mass to be 1.028+0:04-0:03 M_Sun, the radius to be 1.066 +/- 0.012 R_Sun and the age to be 5.25+1:41-1:39 Gyr. We estimate the radius of the 10.6 d planet as 2.37 +/- 0.13 R_Earth. Using 63 radial velocity observations obtained with the HARPS-N spectrograph on the Telescopio Nazionale Galileo and 36 observations made with the HIRES spectrograph at Keck Observatory, we measure the mass of this planet to be 6.8 +/- 1.4M_Earth. We also detect two additional non-transiting companions, a planet with a minimum mass of 4.46 +/- 0.12 M_J in a nearly circular 524 d orbit and a massive companion with a period >10 years and mass >12.1M_J . The twelve exoplanets with radii <2.7 R_Earth and precise mass measurements appear to fall into two populations, with those <1.6 R_Earth following an Earth-like composition curve and larger planets requiring a significant fraction of volatiles. With a density of 2.76 +/- 0.73 g cm-3, Kepler-454b lies near the mass transition between these two populations and requires the presence of volatiles and/or H/He gas.
Citation
Gettel , S , Charbonneau , D , Dressing , C D , Buchhave , L A , Dumusque , X , Vanderburg , A , Bonomo , A S , Malavolta , L , Pepe , F , Cameron , A C , Latham , D W , Udry , S , Marcy , G W , Isaacson , H , Howard , A W , Davies , G R , Aguirre , V S , Kjeldsen , H , Bedding , T R , Lopez , E , Affer , L , Cosentino , R , Figueira , P , Fiorenzano , A F M , Harutyunyan , A , Johnson , J A , Lopez-Morales , M , Lovis , C , Mayor , M , Micela , G , Molinari , E , Motalebi , F , Phillips , D F , Piotto , G , Queloz , D , Rice , K , Sasselov , D , Segransan , D , Sozzetti , A , Watson , C , Basu , S , Campante , T L , Christensen-Dalsgaard , J , Kawaler , S D , Metcalfe , T S , Handberg , R , Lund , M N , Lundkvist , M S , Huber , D & Chaplin , W J 2016 , ' The Kepler-454 system : A small, not-rocky inner planet, a Jovian world, and a distant companion ' , Astrophysical Journal , vol. 816 , no. 2 , 95 . https://doi.org/10.3847/0004-637X/816/2/95
Publication
Astrophysical Journal
Status
Peer reviewed
ISSN
0004-637XType
Journal article
Rights
© 2016. The American Astronomical Society. This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at http://dx.doi.org/10.3847/0004-637X/816/2/95
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Related items
Showing items related by title, author, creator and subject.
-
A prospective new diagnostic technique for distinguishing eruptive and noneruptive active regions
Pagano, Paolo; Mackay, Duncan H.; Yardley, Stephanie L. (2019-09-26) - Journal articleActive regions are the source of the majority of magnetic flux rope ejections that become coronal mass ejections (CMEs). To identify in advance which active regions will produce an ejection is key for both space weather ... -
From dense hot Jupiter to low-density Neptune : the discovery of WASP-127b, WASP-136b, and WASP-138b
Lam, K. W. F.; Faedi, F.; Brown, D. J. A.; Anderson, D. R.; Delrez, L.; Gillon, M.; Hébrard, G.; Lendl, M.; Mancini, L.; Southworth, J.; Smalley, B.; Triaud, A. H. M.; Turner, O. D.; Hay, K. L.; Armstrong, D. J.; Barros, S. C. C.; Bonomo, A. S.; Bouchy, F.; Boumis, P.; Collier Cameron, A.; Doyle, A. P.; Hellier, C.; Henning, T.; Jehin, E.; King, G.; Kirk, J.; Louden, T.; Maxted, P. F. L.; McCormac, J. J.; Osborn, H. P.; Palle, E.; Pepe, F.; Pollacco, D.; Prieto-Arranz, J.; Queloz, D.; Rey, J.; Ségransan, D.; Udry, S.; Walker, S.; West, R. G.; Wheatley, P. J. (2017-03-01) - Journal articleWe report three newly discovered exoplanets from the SuperWASP survey. WASP-127b is a heavily inflated super-Neptune of mass 0.18 ± 0.02 MJ and radius 1.37 ± 0.04 RJ. This is one of the least massive planets discovered by ... -
WASP-80b has a dayside within the T-dwarf range
Triaud, Amaury H. M. J.; Gillon, Michael; Ehrenreich, David; Herrero, Enrique; Lendl, Monika; Anderson, David R.; Cameron, Andrew Collier; Delrez, Laetitia; Demory, Brice-Olivier; Hellier, Coel; Heng, Keving; Jehin, Emmanuel; Maxted, Pierre F. L.; Pollacco, Don; Queloz, Didier; Ribas, Ignasi; Smalley, Barry; Smith, Alexis Michael Sheridan; Udry, Stephane (2015-07-01) - Journal articleWASP-80b is a missing link in the study of exo-atmospheres. It falls between the warm Neptunes and the hot Jupiters and is amenable for characterisation, thanks to its host star's properties. We observed the planet through ...