A Metal-biased Planet Search

TL;DR

This paper reports on a metal-rich planet search using HARPS, aiming to find transiting planets around bright, inactive, metal-rich stars, and presents initial findings of a potential planetary companion with a 5-day orbit.

Contribution

It introduces a new survey targeting bright, metal-rich stars with high-resolution spectroscopy and reports the first candidate detection from this survey.

Findings

Detection of a potential planetary-mass companion with a 5-day period.

Sample of 100 bright, inactive, metal-rich stars characterized.

Initial candidate shows radial velocity consistent with a planet.

Abstract

We have begun a metal-rich planet search project using the HARPS instrument in La Silla, Chile to target planets with a high potential to transit their host star and add to the number of bright benchmark transiting planets. The sample currently consists of 100, bright (7.5 </= V </= 9.5) solar-type stars (0.5 </= B-V </= 0.9) in the southern hemisphere which are both inactive (logR'HK </= -4.5) and metal-rich ([Fe/H] >/= 0.1 dex). We determined the chromospheric activity and metallicity status of our sample using high resolution FEROS spectra. We also introduce the first result from our HARPS planet search and show that the radial-velocity amplitude of this star is consistent with an orbiting planetary-mass companion (i.e. Msini < 0.5MJ) with a period of ~5 days. We are currently engaged in follow-up to confirm this signal as a bonafide orbiting planet.