Publication Date:
2016-05-22
Description:
We report the discovery of KELT-10b, the first transiting exoplanet discovered using the KELT-South telescope. KELT-10b is a highly inflated sub-Jupiter mass planet transiting a relatively bright V = 10.7 star (TYC 8378-64-1), with T eff = 5948 ± 74 K, log g = $4.319_{-0.030}^{+0.020}$ and [Fe/H] = $0.09_{-0.10}^{+0.11}$ , an inferred mass M * = $1.112_{-0.061}^{+0.055}$ M and radius R * = $1.209_{-0.035}^{+0.047}$ R . The planet has a radius R p = $1.399_{-0.049}^{+0.069}$ R J and mass M p = $0.679_{-0.038}^{+0.039}$ M J . The planet has an eccentricity consistent with zero and a semimajor axis a = $0.052\,50_{-0.000\,97}^{+0.000\,86}$ au. The best-fitting linear ephemeris is T 0 = 2457 066.720 45 ± 0.000 27 BJD TDB and P = 4.166 2739 ± 0.000 0063 d. This planet joins a group of highly inflated transiting exoplanets with a larger radius and smaller mass than that of Jupiter. The planet, which boasts deep transits of 1.4 per cent, has a relatively high equilibrium temperature of T eq = $1377_{-23}^{+28}$ K, assuming zero albedo and perfect heat redistribution. KELT-10b receives an estimated insolation of $0.817_{-0.054}^{+0.068}$ x 10 9 erg s –1 cm –2 , which places it far above the insolation threshold above which hot Jupiters exhibit increasing amounts of radius inflation. Evolutionary analysis of the host star suggests that KELT-10b may not survive beyond the current subgiant phase, depending on the rate of in-spiral of the planet over the next few Gyr. The planet transits a relatively bright star and exhibits the third largest transit depth of all transiting exoplanets with V 〈 11 in the Southern hemisphere, making it a promising candidate for future atmospheric characterization studies.
Print ISSN:
0035-8711
Electronic ISSN:
1365-2966
Topics:
Physics
Permalink