A Correlation Between Stellar Activity and the Surface Gravity of Hot Jupiters

Abstract

Recently Knutson et al. (2010) have demonstrated a correlation between the presence of temperature inversions in the atmospheres of hot Jupiters, and the chromospheric activity levels of the host stars. Here we show that there is also a correlation, with greater than 99.5% confidence, between the surface gravity of hot Jupiters and the activity levels of the host stars, such that high surface gravity planets tend be found around high activity stars. We also find a less significant positive correlation between planet mass and chromospheric activity, but no significant correlation is seen between planet radius and chromospheric activity. We consider the possibility that this may be due to an observational bias against detecting lower mass planets around higher activity stars, but conclude that this bias is only likely to affect the detection of planets much smaller than those considered here. Finally, we speculate on physical origins for the correlation, including the possibility that the effect of stellar insolation on planetary radii has been significantly underestimated, that strong UV flux evaporates planetary atmospheres, or that high mass hot Jupiters induce activity in their host stars, but do not find any of these hypotheses to be particularly compelling.

5 pages, 2 figures, 2 tables, submitted to ApJ Letters. Comments welcome.

References in corpus (22)

• Improved parameters for extrasolar transiting planets
• Homogeneous studies of transiting extrasolar planets. I. Light curve analyses
• The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO-3b
• HAT-P-7: A Retrograde or Polar Orbit, and a Third Body
• HAT-P-7b: An Extremely Hot Massive Planet Transiting a Bright Star in the Kepler Field
• WASP-19b: the shortest period transiting exoplanet yet discovered
• WASP-17b: an ultra-low density planet in a probable retrograde orbit
• The Rossiter-McLaughlin effect of CoRoT-3b & HD189733b
• The Discovery of Ellipsoidal Variations in the Kepler Light Curve of HAT-P-7
• HAT-P-12b: A Low-Density Sub-Saturn Mass Planet Transiting a Metal-Poor K Dwarf
• HAT-P-13b,c: a transiting hot Jupiter with a massive outer companion on an eccentric orbit
• Extrasolar Giant Planets and X-ray Activity
• Physical properties of the 0.94-day period transiting planetary system WASP-18
• WASP-14b: 7.3 Mj transiting planet in an eccentric orbit
• VLT transit and occultation photometry for the bloated planet CoRoT-1b
• The AGN and Gas Disk in the Low Surface Brightness Galaxy PGC045080
• HAT-P-14b: A 2.2 Jupiter-mass exoplanet transiting a bright F star
• Refined stellar, orbital and planetary parameters of the eccentric HAT-P-2 planetary system
• Updated parameters for the transiting exoplanet WASP-3b using RISE, a new fast camera for the Liverpool Telescope
• The 0.5M${}_J$ transiting exoplanet WASP-13b
• Magnetic activity in the photosphere of CoRoT-Exo-2a. Active longitudes and short-term spot cycle in a young Sun-like star
• Star-Planet Interactions

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• Ariel stellar characterisation: I -- homogeneous stellar parameters of 187 FGK planet host stars Description and validation of the method
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