Journal article

ASASSN-14ko is a Periodic Nuclear Transient in ESO 253-G003

Anna V Payne, Benjamin J Shappee, Jason T Hinkle, Patrick J Vallely, Christopher S Kochanek, Thomas W-S Holoien, Katie Auchettl, KZ Stanek, Todd A Thompson, Jack MM Neustadt, Michael A Tucker, James D Armstrong, Joseph Brimacombe, Paulo Cacella, Robert Cornect, Larry Denneau, Michael M Fausnaugh, Heather Flewelling, Dirk Grupe, AN Heinze Show all

The Astrophysical Journal | IOP PUBLISHING LTD | Published : 2021

Abstract

We present the discovery that ASASSN-14ko is a periodically flaring active galactic nucleus at the center of the galaxy ESO 253-G003. At the time of its discovery by the All-Sky Automated Survey for Supernovae (ASAS-SN), it was classified as a supernova close to the nucleus. The subsequent 6 yr of V- A nd g-band ASAS-SN observations revealed that ASASSN-14ko has nuclear flares occurring at regular intervals. The 17 observed outbursts show evidence of a decreasing period over time, with a mean period of P 0 = 114.2 ± 0.4 days and a period derivative of. The most recent outburst in 2020 May, which took place as predicted, exhibited spectroscopic changes during the rise and had a UV bright, bla..

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University of Melbourne Researchers

Grants

Awarded by Gordon and Betty Moore Foundation


Awarded by NSF


Awarded by NASA


Awarded by Danish National Research Foundation


Awarded by DOE CSGF


Awarded by FONDECYT


Awarded by Ministry of Economy, Development, and Tourism's Millennium Science Initiative


Awarded by Research Corporation


Awarded by Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)


Funding Acknowledgements

We thank the Las Cumbres Observatory and its staff for its continuing support of the ASAS-SN project. ASAS-SN is supported by the Gordon and Betty Moore Foundation through grant GBMF5490 to the Ohio State University, and NSF grants AST-1515927 and AST-1908570. Development of ASAS-SN has been supported by NSF grant AST-0908816, the Mt. Cuba Astronomical Foundation, the Center for Cosmology and AstroParticle Physics at the Ohio State University, the Chinese Academy of Sciences South America Center for Astronomy (CAS-SACA), and the Villum Foundation.A.V.P. acknowledges support from the NASA Fellowship through grant 80NSSC19K1679. B.J.S., C.S.K., and K.Z.S. are supported by NSF grant AST-1907570. B.J.S. is also supported by NASA grant 80NSSC19K1717 and NSF grants AST1920392 and AST-1911074. C.S.K. and K.Z.S. are supported by NSF grant AST-181440. K.A.A. is supported by the Danish National Research Foundation (DNRF132). M.A.T. acknowledges support from the DOE CSGF through grant DESC0019323. Support for J.L.P. is provided in part by FONDECYT through the grant 1191038 and by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics, MAS. T.A.T. is supported in part by Scialog Scholar grant 24215 from the Research Corporation. Parts of this research were supported by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013.