HATS-39b, HATS-40b, HATS-41b, and HATS-42b: three inflated hot Jupiters and a super-Jupiter transiting F stars

We report the discovery of four transiting hot Jupiters from the HATSouth survey: HATS39b, HATS-40b, HATS-41b, and HATS-42b. These discoveries add to the growing number of transiting planets orbiting moderately bright (12.5 less than or similar to V less than or similar to 13.7) F dwarf stars on short (2-5 d) periods. The planets have similar radii, ranging from 1.33(+0.29) (-0.20) RJ for HATS- 41b to 1.58(+0.16) (-0.12) RJ for HATS-40b. Their masses and bulk densities, however, span more than an order of magnitude. HATS-39b has a mass of 0.63 +/- 0.13M(J), and an inflated radius of 1.57 +/- 0.12 R-J, making it a good target for future transmission spectroscopic studies. HATS41b is a very massive 9.7 +/- 1.6M(J) planet and one of only a few hot Jupiters found to date with a mass over 5 M-J. This planet orbits the highest metallicity star ([Fe/H] = 0.470 +/- 0.010) known to host a transiting planet and is also likely on an eccentric orbit. The highmass, coupled with a relatively young age (1.34(+0.31) (-0.51) Gyr) for the host star, is a factor that may explain why this planet's orbit has not yet circularized.