MASCARA-3b^★

A hot Jupiter transiting a bright F7 star in an aligned orbit

¹ Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
e-mail: hjorth@phys.au.dk
² Institut de Recherche sur les Exoplanètes, Département de Physique, Université de Montréal, Montréal, QC H3C 3J7, Canada
³ Aix-Marseille Univ., CNRS, CNES, LAM, Marseille, France
⁴ Leiden Observatory, Leiden University, Postbus 9513, 2300 RA, Leiden, The Netherlands
⁵ Department of Physics, University of Warwick, Coventry CV4 AL, UK
⁶ Instituto de Astrofísica de Canarias (IAC), Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain
⁷ Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain
⁸ Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA

Received: 12 June 2019
Accepted: 20 August 2019

Abstract

We report the discovery of MASCARA-3b, a hot Jupiter orbiting its bright (V = 8.33) late F-type host every 5.55149 ± 0.00001 days in an almost circular orbit (e = 0.050_−0.017^+0.020). This is the fourth exoplanet discovered with the Multi-site All-Sky CAmeRA (MASCARA), and the first of these that orbits a late-type star. Follow-up spectroscopic measurements were obtained in and out of transit with the Hertzsprung SONG telescope. Combining the MASCARA photometry and SONG radial velocities reveals a radius and mass of 1.36 ± 0.05 R_Jup and 4.2 ± 0.2 M_Jup. In addition, SONG spectroscopic transit observations were obtained on two separate nights. From analyzing the mean out-of-transit broadening function, we obtain v sin i_⋆ = 20.4 ± 0.4 km s⁻¹. In addition, investigating the Rossiter-McLaughlin effect, as observed in the distortion of the stellar lines directly and through velocity anomalies, we find the projected obliquity to be λ = 1.2_−7.4^+8.2 deg, which is consistent with alignment.