An Orbital Stability Study of the Proposed Companions of SW Lyncis

TL;DR

This study uses numerical simulations to test the stability of proposed companions orbiting SW Lyncis, finding that the suggested multi-body system is highly unstable and likely does not exist as previously thought.

Contribution

It provides a systematic dynamical stability analysis of proposed companions around SW Lyncis, challenging prior interpretations based on eclipse timing variations.

Findings

The proposed companions lead to a highly unstable system within 1000 years.

Dynamical analysis suggests the companions likely do not exist or have different orbital properties.

The study demonstrates the importance of stability tests in validating companion hypotheses.

Abstract

We have investigated the dynamical stability of the proposed companions orbiting the Algol type short-period eclipsing binary SW Lyncis (Kim et al. 2010). The two candidate companions are of stellar to sub-stellar nature, and were inferred from timing measurements of the system's primary and secondary eclipses. We applied well-tested numerical techniques to accurately integrate the orbits of the two companions and to test for chaotic dynamical behaviour. We carried out the stability analysis within a systematic parameter survey varying both the geometries and orientation of the orbits of the companions, as well as their masses. In all our numerical integrations we found that the proposed SW Lyn multi-body system is highly unstable on time-scales on the order of 1000 years. Our results cast doubt on the interpretation that the timing variations are caused by two companions. This work demonstrates that a straightforward dynamical analysis can help to test whether a best-fit companion-based model is a physically viable explanation for measured eclipse timing variations. We conclude that dynamical considerations reveal that the propsed SW Lyncis multi-body system most likely does not exist or the companions have significantly different orbital properties as conjectured in Kim et al. (2010).