Low-amplitude and long-period radial velocity variations in giants HD 3574, 63 Cygni, and HD 216946 (Research Note)

TL;DR

This research identifies low-amplitude, long-period radial velocity variations in three evolved giant stars, suggesting potential orbital companions or stellar activity, based on a decade of precise spectroscopic measurements.

Contribution

The study provides new long-term radial velocity data revealing orbital variations in giants HD 3574, 63 Cyg, and HD 216946, expanding understanding of stellar behavior and companion detection.

Findings

Detected long-period radial velocity variations in three giants.

Measured periods of 1061, 982, and 1382 days.

Observed semi-amplitudes of 376, 742, and 699 m/s.

Abstract

Aims. We study the low-amplitude and long-period variations in evolved stars using precise radial velocity measurements. Methods. The high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) was used from September 2004 to May 2014 as part of the exoplanet search program at the Bohyunsan Optical Astronomy Observatory (BOAO). Results. We report the detection of low-amplitude and long-period orbital radial velocity variations in three evolved stars, HD 3574, 63 Cyg, and HD 216946. They have periods of 1061, 982, and 1382 days and semi-amplitudes of 376, 742, and 699 m/s, respectively.