Using HARPS-N to characterize the long-period planets in the PH-2 and Kepler-103 systems
MetadataShow full item record
We present confirmation of the planetary nature of PH-2b, as well as the first mass estimates for the two planets in the Kepler-103 system. PH-2b and Kepler-103c are both long-period and transiting, a sparsely populated category of exoplanets. We use Kepler light-curve data to estimate a radius, and then use HARPS-N radial velocities to determine the semi-amplitude of the stellar reflex motion and, hence, the planet mass. For PH-2b we recover a 3.5σ mass estimate of Mp=109+30−32 M⊕ and a radius of Rp = 9.49 ± 0.16 R⊕. This means that PH-2b has a Saturn-like bulk density and is the only planet of this type with an orbital period P > 200 d that orbits a single star. We find that Kepler-103b has a mass of Mp,b=11.7+4.31−4.72 M⊕ and Kepler-103c has a mass of Mp,c=58.5+11.2−11.4 M⊕. These are 2.5σ and 5σ results, respectively. With radii of Rp,b=3.49+0.06−0.05 R⊕ and Rp,c=5.45+0.18−0.17 R⊕, these results suggest that Kepler-103b has a Neptune-like density, while Kepler-103c is one of the highest density planets with a period P > 100 d. By providing high-precision estimates for the masses of the long-period, intermediate-mass planets PH-2b and Kepler-103c, we increase the sample of long-period planets with known masses and radii, which will improve our understanding of the mass–radius relation across the full range of exoplanet masses and radii.
Dubber , S C , Mortier , A , Rice , K , Nava , C , Malavolta , L , Giles , H , Coffinet , A , Charbonneau , D , Vanderburg , A , Bonomo , A S , Boschin , W , Buchhave , L A , Cameron , A C , Cosentino , R , Dumusque , X , Ghedina , A , Harutyunyan , A , Haywood , R D , Latham , D , López-Morales , M , Micela , G , Molinari , E , Pepe , F A , Phillips , D , Piotto , G , Poretti , E , Sasselov , D , Sozzetti , A & Udry , S 2019 , ' Using HARPS-N to characterize the long-period planets in the PH-2 and Kepler-103 systems ' , Monthly Notices of the Royal Astronomical Society , vol. 490 , no. 4 , pp. 5103–5121 . https://doi.org/10.1093/mnras/stz2856
Monthly Notices of the Royal Astronomical Society
Copyright © 2019 the Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the final published version of the work, which was originally published at https://doi.org/10.1093/mnras/stz2856
DescriptionFunding: Senior Kavli Institute Fellowships at the University of Cambridge (AM); UK Science & Technology Facilities Council (STFC) consolidated grant number ST/R000824/1 (ACC).
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.