MASCARA-4 b/bRing-1b - A retrograde hot Jupiter around the bright A3V star HD 85628

Abstract

In this paper, we aim to characterize a transiting planetary candidate in the southern skies found in the combined MASCARA and bRing data sets of HD 85628, an A3V star of V = 8.2 mag at a distance 172 pc, to confirm its planetary nature. The candidate was originally detected in data obtained jointly with the MASCARA and bRing instruments using a BLS search for transit events. Further photometry was taken by the 0.7 m CHAT, and radial velocity measurements with FIDEOS on the ESO 1.0 m Telescope. High resolution spectra during a transit were taken with CHIRON on the SMARTS 1.5 m telescope to target the Doppler shadow of the candidate. We confirm the existence of a hot Jupiter transiting the bright A3V star HD 85628, which we co-designate as MASCARA-4b and bRing-1b. It is in a 2.824 day orbit, with an estimated planet radius of $1.53_{0.04}^{0.07}$ $R_{\mathrm{Jup}}$ and an estimated planet mass of $3.1\pm 0.9$ $M_{\mathrm{Jup}}$, putting it well within the planet mass regime.. The CHAT observations show a partial transit, reducing the probability that the transit was around a faint background star. The CHIRON observations show a clear Doppler shadow, implying that the transiting object is in a retrograde orbit with $|\lambda |=247.5\pm 1.6$\textdegree. The planet orbits at at a distance of 0.047 $\pm$ 0.004 AU from the star and has a zero-albedo equilibrium temperature of 2100 $\pm$ 100 K. In addition, we find that HD 85628 has a previously unreported stellar companion star in the Gaia DR2 data demonstrating common proper motion and parallax at 4.3 arcsecond separation (projected separation $\sim$740 AU), and with absolute magnitude consistent with being a K/M dwarf.

arXiv comment10 pages, 8 figures, submitted to A&A

References in corpus (56)

• emcee: The MCMC Hammer
• Gaia Data Release 2. Summary of the contents and survey properties
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• The Transiting Exoplanet Survey Satellite
• Evolutionary tracks and isochrones for low- and intermediate-mass stars: from 0.15 to 7 M_sun, and from Z=0.0004 to 0.03
• Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-Main Sequence Stars
• Analytic Lightcurves for Planetary Transit Searches
• The USNO-B Catalog
• Detection of Planetary Transits Across a Sun-like Star
• The WASP Project and the SuperWASP Cameras
• batman: BAsic Transit Model cAlculatioN in Python
• A box-fitting algorithm in the search for periodic transits
• Gaia Data Release 2: Photometric content and validation
• Hot Stars with Hot Jupiters Have High Obliquities
• Obliquities of Hot Jupiter host stars: Evidence for tidal interactions and primordial misalignments
• Origins of Hot Jupiters
• Wide-field millimagnitude photometry with HAT: A Tool for Extra-solar Planet Detection
• Homogeneous studies of transiting extrasolar planets. IV. Thirty systems with space-based light curves
• The Transiting Exoplanet Survey Satellite: Simulations of planet detections and astrophysical false positives
• ELODIE metallicity-biased search for transiting Hot Jupiters II. A very hot Jupiter transiting the bright K star HD189733
• The Kilodegree Extremely Little Telescope (KELT): A Small Robotic Telescope for Large-Area Synoptic Surveys
• The Frequency of Hot Jupiters Orbiting Nearby Solar-Type Stars
• Line-profile tomography of exoplanet transits -- II. A gas-giant planet transiting a rapidly-rotating A5 star
• Evidence of Possible Spin-Orbit Misalignment Along the Line of Sight in Transiting Exoplanet Systems
• A giant planet undergoing extreme ultraviolet irradiation by its hot massive-star host
• Rotational velocities of A-type stars IV. Evolution of rotational velocities
• Three-dimensional mapping of the local interstellar medium with composite data
• Exploring Exoplanet Populations with NASA's Kepler Mission
• Atomic iron and titanium in the atmosphere of the exoplanet KELT-9b
• CERES: A Set of Automated Routines for Echelle Spectra
• Scaled solar tracks and isochrones in a large region of the Z-Y plane. II. From 2.5 to 20 solar masses
• Transiting exoplanets from the CoRoT space mission I - CoRoT-Exo-1b: a low-density short-period planet around a G0V star
• Spin-Orbit Evolution Of Short-Period Planets
• An extended hydrogen envelope of the extremely hot giant exoplanet KELT-9b
• The XO Project: Searching for Transiting Extra-solar Planet Candidates
• All-Sky spectrally matched UBVRI-ZY and u'g'r'i'z' magnitudes for stars in the Tycho2 catalog
• The Rossiter-McLaughlin effect reloaded: Probing the 3D spin-orbit geometry, differential stellar rotation, and the spatially-resolved stellar spectrum of star-planet systems
• High-Resolution Spectroscopic Detection of TiO and Stratosphere in the Day-side of WASP-33b
• Main-Sequence Effective Temperatures from a Revised Mass-Luminosity Relation Based on Accurate Properties
• Orbital misalignment of the Neptune-mass exoplanet GJ 436b with the spin of its cool star
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) I. Detection of hot neutral sodium at high altitudes on WASP-49b
• MASCARA-2 b: A hot Jupiter transiting the $m_V=7.6$ A-star HD185603
• The Multi-site All-Sky CAmeRA: Finding transiting exoplanets around bright ($m_V<8$) stars
• A Nearly Polar Orbit for the Extrasolar Hot Jupiter WASP-79b
• HATS-60b - HATS-69b: Ten Transiting Planets From HATSouth
• Doppler tomography of transiting exoplanets: A prograde, low-inclined orbit for the hot Jupiter CoRoT-11b
• Refined architecture of the WASP-8 system: a cautionary tale for traditional Rossiter-McLaughlin analysis
• HATS-54b-HATS-58Ab: five new transiting hot Jupiters including one with a possible temperate companion
• Precision stellar radial velocity measurements with FIDEOS at the ESO 1-m telescope of La Silla
• K2-287b: an Eccentric Warm Saturn transiting a G-dwarf
• bRing: An observatory dedicated to monitoring the $\beta$ Pictoris b Hill sphere transit
• Ground-based search for the brightest transiting planets with the Multi-site All-Sky CAmeRA - MASCARA
• MASCARA-3b: A hot Jupiter transiting a bright F7 star in an aligned orbit
• Discovery of δ Scuti Pulsations in the Young Hybrid Debris Disk Star HD 156623
• Data calibration for the MASCARA and bRing instruments
• Bright Southern Variable Stars in the bRing Survey

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• Spi-OPS: Spitzer and CHEOPS confirm the near-polar orbit of MASCARA-1 b and reveal a hint of dayside reflection
• DREAM II. The spin-orbit angle distribution of close-in exoplanets under the lens of tides
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• The Habitable Zones of Rapidly Rotating Main Sequence A/F Stars
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