2014/10/13 by D. R. Anderson, D. J. A. Brown, Anderson, D. R. +45
Physics and Astronomy · #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #astro-ph.EP
paper · pdf · doi:10.48550/arxiv.1410.3449
14 pages, 12 figures, 6 tables, submitted to MNRAS. UPDATE: Fixed typos in declination and vsini of WASP-112
arxiv created 2014/10/14 · arxiv updated 2014/10/15
We present the discoveries of six transiting hot Jupiters: WASP-87b, WASP-108b, WASP-109b, WASP-110b, WASP-111b and WASP-112b. The planets have masses of 0.51--2.2 M\rm Jup and radii of 1.19--1.44 R\rm Jup and are in orbits of 1.68--3.78 d around stars with masses 0.81--1.50 M\rm \odot. WASP-111b is in a prograde, near-aligned (λ= -5 ± 16^∘), near-circular (e < 0.10 at 2 σ) orbit around a mid-F star. As tidal alignment around such a hot star is thought to be inefficient, this suggests that either the planet migrated inwards through the protoplanetary disc or that scattering processes happened to leave it in a near-aligned orbit. WASP-111 appears to have transitioned from an active to a quiescent state between the 2012 and 2013 seasons, which makes the system a candidate for studying the effects of variable activity on a hot-Jupiter atmosphere. We find evidence that the mid-F star WASP-87 is a visual binary with a mid-G star. Two host stars are metal poor: WASP-112 has [Fe/H] = -0.64 ± 0.15 and WASP-87 has [Fe/H] = -0.41 ± 0.10. The low density of WASP-112 (0.81 M\rm \odot, 0.80 ± 0.04 ρ\rm \odot) cannot be matched by standard models for any reasonable value of the age of the star, suggesting it to be affected by the "radius anomaly".