Planetary Companion in K Giant σ Persei
Abstract
We report the detection of an exoplanet candidate in orbit around sigma Persei from a radial velocity (RV) survey. The system exhibits periodic RV variations of 579.8 +/- 2.4 days. The purpose of the survey is to search for low-amplitude and long-period RV variations in giants and examine the origin of the variations using the fiber-fed Bohyunsan Observatory Echelle Spectrograph installed at the 1.8-m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We present high-accuracy RV measurements of sigma Per made from December 2003 to January 2014. We argue that the RV variations are not related to the surface inhomogeneities but instead a Keplerian motion of the planetary companion is the most likely explanation. Assuming a stellar mass of 2.25 +/- 0.5 M_Sun, we obtain a minimum planetary companion mass of 6.5 +/- 1.0 M_Jup, with an orbital semi-major axis of 1.8 +/- 0.1 AU, and an eccentricity of 0.3 +/- 0.1 around sigma Per.
- Publication:
-
Journal of Korean Astronomical Society
- Pub Date:
- April 2014
- DOI:
- 10.5303/JKAS.2014.47.2.69
- arXiv:
- arXiv:1405.2130
- Bibcode:
- 2014JKAS...47...69L
- Keywords:
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- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 9 pages, 6 fiures, 3 tables