A cyclical period variation detected in the updated orbital period analysis of TV Columbae

TL;DR

This study detects a cyclical variation in the orbital period of TV Columbae, suggesting the presence of a low-mass tertiary companion influencing its orbital dynamics.

Contribution

The paper provides updated eclipse timings and identifies a cyclical period variation, proposing a light travel-time effect caused by a potential low-mass third body.

Findings

Detected a ~31-year cyclical period variation in TV Columbae.

Corrected previous orbital ephemeris based on new eclipse timings.

Suggested a low-mass tertiary companion as the cause of the period variation.

Abstract

The two CCD photometries of the intermediate polar TV Columbae are made for obtaining the two updated eclipse timings with high precision. There is an interval time \sim 17yr since the last mid-eclipse time observed in 1991. Thus, the new mid-eclipse times can offer an opportunity to check the previous orbital ephemerides. A calculation indicates that the orbital ephemeris derived by Augusteijn et al. (1994) should be corrected. Based on the proper linear ephemeris (Hellier, 1993), the new orbital period analysis suggests a cyclical period variation in the O-C diagram of TV Columbae. Using Applegate's mechanism to explain the periodic oscillation in O-C diagram, the required energy is larger than that a M0-type star can afford over a complete variation period \sim 31.0(\pm 3.0)yr. Thus, the light travel-time effect indicates that the tertiary component in TV Columbae may be a dwarf with a low mass, which is near the mass lower limit \sim 0.08Msun as long as the inclination of the third body high enough.