KELT-14b and KELT-15b: An Independent Discovery of WASP-122b and a New Hot Jupiter

Abstract

We report the discovery of KELT-14b and KELT-15b, two hot Jupiters from the KELT-South survey. KELT-14b, an independent discovery of the recently announced WASP-122b, is an inflated Jupiter mass planet that orbits a $\sim 5.0_{-0.7}^{+0.3}$ Gyr, $V$ = 11.0, G2 star that is near the main sequence turnoff. The host star, KELT-14 (TYC 7638-981-1), has an inferred mass $M_{\ast }$=$1.18_{-0.07}^{+0.05}$$M_{\odot }$ and radius $R_{\ast }$=$1.37\pm -0.08$$R_{\odot }$, and has $T_{eff}$=$5802_{-92}^{+95}$K, $\log g_{\ast }$=$4.23_{-0.04}^{+0.05}$ and =$0.33\pm 0.09$. The planet orbits with a period of $1.7100588\pm 0.0000025$ days ($T_0$=2457091.02863$\pm$0.00047) and has a radius R${}_p$=$1.52_{-0.11}^{+0.12}$$R_J$ and mass M${}_p$=$1.196\pm 0.072$$M_J$, and the eccentricity is consistent with zero. KELT-15b is another inflated Jupiter mass planet that orbits a $\sim$ $4.6_{-0.4}^{+0.5}$ Gyr, $V$ = 11.2, G0 star (TYC 8146-86-1) that is near the "blue hook" stage of evolution prior to the Hertzsprung gap, and has an inferred mass $M_{\ast }$=$1.181_{-0.050}^{+0.051}$$M_{\odot }$ and radius $R_{\ast }$=$1.48_{-0.04}^{+0.09}$$R_{\odot }$, and $T_{eff}$=$6003_{-52}^{+56}$K, $\log g_{\ast }$=$4.17_{-0.04}^{+0.02}$ and [Fe/H]=$0.05\pm 0.03$. The planet orbits on a period of $3.329441\pm 0.000016$ days ($T_0$ = 2457029.1663$\pm$0.0073) and has a radius R${}_p$=$1.443_{-0.057}^{+0.11}$$R_J$ and mass M${}_p$=$0.91_{-0.22}^{+0.21}$$M_J$ and an eccentricity consistent with zero. KELT-14b has the second largest expected emission signal in the K-band for known transiting planets brighter than $K<10.5$. Both KELT-14b and KELT-15b are predicted to have large enough emission signals that their secondary eclipses should be detectable using ground-based observatories.

15 pages, 11 figures, 9 tables, Accepted for publication in AJ