Spectroscopic orbits of subsystems in multiple stars. VI

TL;DR

This paper reports new spectroscopic orbits for 13 late-type stars in multiple systems, analyzing their orbital parameters, component masses, and rotation, contributing to understanding the dynamics of hierarchical stellar systems.

Contribution

It provides 13 new spectroscopic orbits of late-type stars in multiple systems, expanding the data on their orbital characteristics and system configurations.

Findings

Most systems are inner subsystems in hierarchical multiples.

Orbital periods range from 2.2 to 1131 days.

The period-eccentricity distribution is smooth, with no features around the tidal circularization period.

Abstract

Thirteen spectroscopic orbits of late-type stars are determined from the high-resolution spectra taken with the CHIRON echelle spectrometer at the 1.5-m CTIO telescope. Most (HIP 14194B, 40523A, 41171A, 51578A, 57572B, 59426A, 62852B, 66438A, 87813B, and 101472A) are inner subsystems in hierarchical multiple stars with three or four components. The periods range from 2.2 to 1131 days. Masses of the components, orbital inclinations, and projected rotation velocities are estimated, the presence or absence of the lithium line is noted. In addition to those systems, HIP 57021 is a simple 54-day twin binary, and HIP 111598 is a compact triple-lined system with periods of 5.9 and 271 days. This object is likely old, but, nevertheless, the secondary component in the inner pair does not rotate synchronously with the orbit. The period-eccentricity diagram of 528 known inner low-mass spectroscopic subsystems (including 36 from this paper series) is given. The distribution of the inner periods is smooth, without any details around the tidal circularization period of ~10 d.