Improved Orbital Parameters and Transit Monitoring for HD 156846b

Abstract

HD 156846b is a Jovian planet in a highly eccentric orbit (e = 0.85) with a period of 359.55 days. The pericenter passage at a distance of 0.16 AU is nearly aligned to our line of sight, offering an enhanced transit probability of 5.4% and a potentially rich probe of the dynamics of a cool planetary atmosphere impulsively heated during close approach to a bright star (V = 6.5). We present new radial velocity (RV) and photometric measurements of this star as part of the Transit Ephemeris Refinement and Monitoring Survey (TERMS). The RV measurements from Keck-HIRES reduce the predicted transit time uncertainty to 20 minutes, an order of magnitude improvement over the ephemeris from the discovery paper. We photometrically monitored a predicted transit window under relatively poor photometric conditions, from which our non-detection does not rule out a transiting geometry. We also present photometry that demonstrates stability at the millimag level over its rotational timescale.

7 pages, 4 figures, accepted for publication in ApJ

References in corpus (18)

• Mass-Radius Relationships for Solid Exoplanets
• Chromospheric Activity and Jitter Measurements for 2630 Stars on the California Planet Search
• Exoplanet Atmospheres
• Prospects for the Characterization and Confirmation of Transiting Exoplanets via the Rossiter-McLaughlin Effect
• Transit timing effects due to an exomoon
• Multi-Wavelength Constraints on the Day-Night Circulation Patterns of HD 189733b
• Transiting exoplanets from the CoRoT space mission I - CoRoT-Exo-1b: a low-density short-period planet around a G0V star
• Efficient fitting of multiplanet Keplerian models to radial velocity and astrometry data
• Photometric and spectroscopic detection of the primary transit of the 111-day-period planet HD 80606 b
• Mass constraints on substellar companion candidates from the re-reduced Hipparcos intermediate astrometric data: Nine confirmed planets and two confirmed brown dwarfs
• The CORALIE survey for southern extra-solar planets XV. Discovery of two eccentric planets orbiting HD4113 and HD156846
• HD 17156b: A Transiting Planet with a 21.2 Day Period and an Eccentric Orbit
• Constraining Orbital Parameters Through Planetary Transit Monitoring
• Transiting planets - lightcurve analysis for eccentric orbits
• Hydrodynamic Simulations of Unevenly Irradiated Jovian Planets
• The upper atmosphere of the exoplanet HD209458b revealed by the sodium D lines: Temperature-pressure profile, ionization layer, and thermosphere
• Photometric Phase Variations of Long-Period Eccentric Planets
• On the Transit Potential of the Planet Orbiting iota Draconis

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