Study of the peculiar variable star Khavchenko 1

TL;DR

This study investigates the unusual variability of star Khavchenko 1, analyzing its light curve and proposing models to explain its behavior, with ongoing observations needed to predict potential eruptions.

Contribution

It provides the first detailed analysis of Khavchenko 1's light curve and suggests possible models for its peculiar variability, expanding understanding of such rare stellar phenomena.

Findings

Star exhibits 0.4 magnitude variability with a 4.213-day period.

Light curve shows cyclic amplitude variations.

Possible models explain the star's unusual behavior.

Abstract

The work is devoted to the study of the peculiar variable star Khavchenko 1 in Auriga. It was discovered by the 7th grade student Sergey Khavchenko in 2020. The brightness of the star varies with an amplitude of about 0.4 magnitude and the period of 4.213 days. Initially the star could not have been attributed to any known type of variability. Its light curve looks like the upside-down light curve of the eclipsing binary similar to that of luminous red nova V1309 Scorpii a few years before the eruption. The analysis of the new data from the ZTF project gathered from 2020 till 2024 has shown the cyclic variations of the light curve amplitude. We have proposed several possible models of this system which can explain such an unusual behavior of this star. The continued observations of this star are necessary to reveal the period changes and to estimate the possible eruption date.