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arXiv · 1907.10609

The ASAS-SN Catalog of Variable Stars V: Variables in the Southern Hemisphere

T. Jayasinghe·K. Z. Stanek·C. S. Kochanek·B. J. Shappee·T. W. -S. Holoien·Todd A. Thompson·J. L. Prieto·Subo Dong·M. Pawlak·O. Pejcha·J. V. Shields·G. Pojmanski·S. Otero·N. Hurst·C. A. Britt·D. Will
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Abstract

The All-Sky Automated Survey for Supernovae (ASAS-SN) provides long baseline (${\sim}4$ yrs) light curves for sources brighter than V$\lesssim17$ mag across the whole sky. As part of our effort to characterize the variability of all the stellar sources visible in ASAS-SN, we have produced ${\sim}30.1$ million V-band light curves for sources in the southern hemisphere using the APASS DR9 catalog as our input source list. We have systematically searched these sources for variability using a pipeline based on random forest classifiers. We have identified ${\sim} 220,000$ variables, including ${\sim} 88,300$ new discoveries. In particular, we have discovered ${\sim}48,000$ red pulsating variables, ${\sim}23,000$ eclipsing binaries, ${\sim}2,200$ $δ$-Scuti variables and ${\sim}10,200$ rotational variables. The light curves and characteristics of the variables are all available through the ASAS-SN variable stars database (https://asas-sn.osu.edu/variables). The pre-computed ASAS-SN V-band light curves for all the ${\sim}30.1$ million sources are available through the ASAS-SN photometry database (https://asas-sn.osu.edu/photometry). This effort will be extended to provide ASAS-SN light curves for sources in the northern hemisphere and for V$\lesssim17$ mag sources across the whole sky that are not included in APASS DR9.

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T. Jayasinghe, K. Z. Stanek, C. S. Kochanek, B. J. Shappee, T. W. -S. Holoien, Todd A. Thompson, J. L. Prieto, Subo Dong, M. Pawlak, O. Pejcha, J. V. Shields, G. Pojmanski, S. Otero, N. Hurst, C. A. Britt, D. Will. 2021-02-23. The ASAS-SN Catalog of Variable Stars V: Variables in the Southern Hemisphere. https://doi.org/10.1093/mnras%2Fstz2711

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