Possible candidates for multiple occurrence of variable stars in the VSX catalogue

TL;DR

This study identifies potential duplicate variable stars in the VSX catalog by analyzing angular proximity and period similarity, revealing nearly 1500 high-probability pairs, including 354 definite duplicates, with distribution patterns across the sky.

Contribution

The paper introduces a systematic method for detecting duplicate variable stars in the VSX catalog using angular distance and period analysis, including considerations of period misclassification.

Findings

1487 candidate pairs with high probability of duplication

354 pairs identified as definite duplicates with identical periods

Distribution of duplicates shows non-uniform sky coverage, especially depression in the Galactic plane

Abstract

A paper about variable stars with possible multiple occurrence in the VSX catalogue is presented. Our main criteria for identification of such duplicities were the angular distance among stars (below 1 arcmin) and close periods of objects. In our approach, we also considered double or half values of periods to reveal possible misclassification among stars with similar light curve shapes. The probability of false identification is expressed by the parameter R giving the relative difference between periods. We found 1487 pairs of stars in angular distance lower than 1 arcmin with period difference R lower than 0.1 %, which are high-probable candidates on duplicates. From this sample, 354 pairs have exactly the same periods (R = 0.0 %) and should be considered as definite duplicates. The main contribution of certain duplicates comes from the Catalina Sky Survey (73 pairs have two names with CSS acronym) and from the BEST projects (71 pairs). Distribution of identified duplicates on the sky is not homogeneous but contains surprising depression in Galactic plane.