On the True Nature of the Contact Binary CRTS J192848.7-404555

TL;DR

This study clarifies that CRTS J192848.7-404555 is a low mass contact binary with specific characteristics, correcting previous assumptions of it being a merger candidate based on survey data.

Contribution

The paper reveals the true nature of CRTS J192848.7-404555 through follow-up photometry, correcting prior misclassification caused by blended survey photometry.

Findings

The system is a low mass contact binary with a high mass ratio of 0.425.

It exhibits a high amplitude of 0.69 magnitude and 24% contact.

The system shows no signs of orbital instability or merger potential.

Abstract

CRTS J192848.7-404555 was recognised as a potential contact binary merger candidate on the basis of survey photometry analysis. We have carried out follow up ground based photometry of the system and show that at the recorded coordinates for the system there are two stars approximately 3 seconds of arc apart. Our analysis shows that the fainter of the two stars is the actual variable while the slightly brighter star is of fixed brightness. In addition we show that the reported survey photometry is the result of both stars being treated as a single light source with resultant erroneous light curve solution. The true nature of CRTS J192848.7-404555 shows it to be a low mass contact binary system with a high mass ratio of 0.425, high amplitude of 0.69 magnitude and shallow 24% contact. The system does not have features of orbital instability and is not a potential merger progenitor.