TRIMOR - three-dimensional correlation technique to analyze multi-order spectra of triple stellar systems; Application to HD188753

TL;DR

TRIMOR is a new three-dimensional correlation algorithm that analyzes multi-order spectra of triple star systems, enabling detection of faint companions and precise measurement of their velocities, leading to improved system characterization.

Contribution

The paper introduces TRIMOR, an extension of TRICOR, specifically designed for multi-order spectra of triple systems, enhancing detection and measurement capabilities for faint stellar companions.

Findings

Successfully applied TRIMOR to HD188753, detecting the faintest star.

Derived the radial velocities and mass ratio of the close pair.

Confirmed the close to coplanar configuration of the triple system.

Abstract

This paper presents a new algorithm, TRIMOR, to analyse multi-order spectra of triple systems. The algorithm is an extension of TRICOR, the three-dimensional correlation technique that derives the radial velocities of triple stellar systems from single-order spectra. The combined correlation derived from many orders enables the detection and the measurement of radial velocities of faint tertiary companions. The paper applied TRIMOR to the already available spectra of HD188753, a well known triple system, yielding the radial velocities of the faintest star in the system. This rendered the close pair of the triple system a double-lined spectroscopic binary, which led to a precise mass-ratio and an estimate of its inclination. The close-pair inclination is very close to the inclination of the wide orbit, consistent with the assertion that this triple system has a close to coplanar configuration.