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arXiv · 2507.19594

A Systematic Search for Big Dippers in ASAS-SN

B. JoHantgen·D. M. Rowan·R. Forés-Toribio·C. S. Kochanek·K. Z. Stanek·B. J. Shappee·Subo Dong·J. L. Prieto·Todd A. Thompson
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Abstract

Dipper stars are extrinsically variable stars with deep dimming events due to extended, often dusty, structures produced by a wide range of mechanisms such as collisions, protoplanetary evolution or stellar winds. ASAS-SN has discovered 12 dipper-like objects as part of its normal operations. Here we systematically search the $\sim 5.1$ million ASAS-SN targets with $13<g<14$~mag for dippers with $\Delta g\ge0.3$~mag to identify 4 new candidates. We also discover 15 long-period eclipsing binary candidates. We characterized the 19 new and 12 previously discovered objects using the ASAS-SN light curves and archival multi-wavelength data. We divide them into three categories: long-period eclipsing binaries with a single eclipse (13 total), long-period eclipsing binaries with multiple eclipses (7 total) and dipper stars with dust or disk occultations (11 total).

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B. JoHantgen, D. M. Rowan, R. Forés-Toribio, C. S. Kochanek, K. Z. Stanek, B. J. Shappee, Subo Dong, J. L. Prieto, Todd A. Thompson. 2025-07-25. A Systematic Search for Big Dippers in ASAS-SN. https://doi.org/10.33232/001c.156224

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