The ASAS-SN Catalog of Variable Stars I: The Serendipitous Survey

TL;DR

The paper presents a comprehensive catalog of over 66,000 new variable stars discovered by the ASAS-SN survey, utilizing automated classification and visual verification, significantly expanding the known variable star population.

Contribution

This work provides the first large-scale, all-sky catalog of variable stars identified through the ASAS-SN survey, including both periodic and irregular variables, with publicly available light curves.

Findings

Discovered 66,179 new variable stars.

Classified variables into periodic and irregular types.

Provided accessible light curves through the ASAS-SN database.

Abstract

The All-Sky Automated Survey for Supernovae (ASAS-SN) is the first optical survey to routinely monitor the whole sky with a cadence of $\sim2-3$ days down to V$\lesssim17$ mag. ASAS-SN has monitored the whole sky since 2014, collecting $\sim100-500$ epochs of observations per field. The V-band light curves for candidate variables identified during the search for supernovae are classified using a random forest classifier and visually verified. We present a catalog of 66,179 bright, new variable stars discovered during our search for supernovae, including 27,479 periodic variables and 38,700 irregular variables. V-band light curves for the ASAS-SN variables are available through the ASAS-SN variable stars database (https://asas-sn.osu.edu/variables). The database will begin to include the light curves of known variable stars in the near future along with the results for a systematic, all-sky variability survey.