The ASAS-SN Catalog of Variable Stars II: <i>Uniform Classification of 412,000 Known Variables</i>

Abstract

The variable stars in the VSX catalog are derived from a multitude of\ninhomogeneous data sources and classification tools. This inhomogeneity\ncomplicates our understanding of variable star types, statistics, and\nproperties, and it directly affects attempts to build training sets for current\n(and next) generation all-sky, time-domain surveys. We homogeneously analyze\nthe ASAS-SN V-band light curves of ${\\sim}412,000$ variables from the VSX\ncatalog. The variables are classified using an updated random forest classifier\nwith an $F_1$ score of 99.4\\% and refinement criteria for individual\nclassifications. We have derived periods for ${\\sim}52,000$ variables in the\nVSX catalog that lack a period, and have reclassified ${\\sim} 17,000$ sources\ninto new broad variability groups with high confidence. We have also\nreclassified ${\\sim} 94,000$ known variables with miscellaneous/generic\nclassifications. The light curves, classifications, and a range of properties\nof the variables are all available through the ASAS-SN variable stars database\n(https://asas-sn.osu.edu/variables). We also include the V-band light curves\nfor a set of ${\\sim}4,000$ rare variables and transient sources, including\ncataclysmic variables, symbiotic binaries and flare stars.\n