Search for exoplanets around northern circumpolar stars

V. Three likely planetary companions to the giant stars HD 19615, HD 150010, and HD 174205

¹ Antbridge Technology, 79-1, 101 Gajeong-ro Yuseong-gu, Daejeon 34120, Korea
e-mail: tlotv1@gmail.com
² Korea Astronomy and Space Science Institute, 776, Daedeokdae-Ro, Youseong-Gu, Daejeon 34055, Korea
e-mail: [bclee;iwhan]@kasi.re.kr
³ Korea University of Science and Technology, Gajeong-ro Yuseong-gu, Daejeon 34113, Korea
⁴ Department of Astronomy and Atmospheric Sciences, Kyungpook National University, Daegu 41566, Korea

Received: 6 October 2021
Accepted: 8 November 2021

Abstract

Aims. We report the detection of long-period radial velocity (RV) variations in three giant stars, HD 19615, HD 150010, and HD 174205, using precise RV measurements.

Methods. These detections are part of the Search for Exoplanets around Northern Circumpolar Stars (SENS) survey being conducted at the Bohyunsan Optical Astronomy Observatory (BOAO). The nature of the RV variations was investigated by analyzing the photometric and line shape variations. We found no variability with the RV period in these quantities and conclude that the RV variations are most likely caused by planetary companions.

Results. Orbital solutions for the three stars yield orbital periods of 402 d, 562 d, and 582 d and minimum masses of 8.5 M_J, 2.4 M_J, and 4.2 M_J, respectively. These masses and periods are typical for planets around intermediate-mass stars, although some unclear interpretations and recent studies may being calling some planet convictions into question. Nevertheless, the SENS program is contributing to our knowledge of giant planets around intermediate-mass stars.