HATS-36b and 24 other transiting/eclipsing systems from the HATSouth - K2 Campaign 7 program

HATS-36b and 24 other transiting/eclipsing systems from the HATSouth - K2 Campaign 7 program

Authors:

Bayliss et al

Abstract:
We report on the result of a campaign to monitor 25 HATSouth candidates using the K2 space telescope during Campaign 7 of the K2 mission. We discover HATS-36b (EPIC 215969174b), a hot Jupiter with a mass of 2.79±0.40 MJ and a radius of 1.263±0.045 RJ which transits a solar-type G0V star (V=14.386) in a 4.1752d period. We also refine the properties of three previously discovered HATSouth transiting planets (HATS-9b, HATS-11b, and HATS-12b) and search the K2 data for TTVs and additional transiting planets in these systems. In addition we also report on a further three systems that remain as Jupiter-radius transiting exoplanet candidates. These candidates do not have determined masses, however pass all of our other vetting observations. Finally we report on the 18 candidates which we are now able to classify as eclipsing binary or blended eclipsing binary systems based on a combination of the HATSouth data, the K2 data, and follow-up ground-based photometry and spectroscopy. These range in periods from 0.7 days to 16.7 days, and down to 1.5 mmag in eclipse depths. Our results show the power of combining ground-based imaging and spectroscopy with higher precision space-based photometry, and serve as an illustration as to what will be possible when combining ground-based observations with TESS data.

The hot Jupiters HATS-11b and HATS-12b

HATS-11b and HATS-12b: Two transiting Hot Jupiters orbiting sub-solar metallicity stars selected for the K2 Campaign 7

Authors:

Rabus et al

Abstract:

We report the discovery of two transiting extrasolar planets from the HATSouth survey. HATS-11, a V=14.1 G0-star shows a periodic 12.9 mmag dip in its light curve every 3.6192 days and a radial velocity variation consistent with a Keplerian orbit. HATS-11 has a mass of 1.000 ± 0.060 M⊙, a radius of 1.444 ± 0.057 M⊙ and an effective temperature of 6060 ± 150 K, while its companion is a 0.85 ± 0.12 MJ, 1.510 ± 0.078 RJ planet in a circular orbit. HATS-12 shows a periodic 5.1 mmag flux decrease every 3.1428 days and Keplerian RV variations around a V=12.8 F-star. HATS-12 has a mass of 1.489 ± 0.071 M⊙, a radius of 2.21 ± 0.21 R⊙, and an effective temperature of 6408 ± 75 K. For HATS-12, our measurements indicate that this is a 2.38 ± 0.11 MJ, 1.35 ± 0.17 RJ planet in a circular orbit. Both host stars show sub-solar metallicity of -0.390 ± 0.060 dex and -0.100 ± 0.040 dex, respectively and are (slightly) evolved stars. In fact, HATS-11 is amongst the most metal-poor and, HATS-12 is amongst the most evolved stars hosting a hot Jupiter planet. Importantly, HATS-11 and HATS-12 have been observed in long cadence by Kepler as part of K2 campaign 7 (EPIC216414930 and EPIC218131080 respectively).