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arXiv · 1405.1417

ASASSN-14ae: A Tidal Disruption Event at 200 Mpc

Thomas W. -S. Holoien·J. L. Prieto·D. Bersier·C. S. Kochanek·K. Z. Stanek·B. J. Shappee·D. Grupe·U. Basu·J. F. Beacom·J. Brimacombe·J. S. Brown·A. B. Davis·J. Jencson·G. Pojmanski·D. M. Szczygiel
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Abstract

ASASSN-14ae is a candidate tidal disruption event (TDE) found at the center of SDSS J110840.11+340552.2 ($d\simeq200$~Mpc) by the All-Sky Automated Survey for Supernovae (ASAS-SN). We present ground-based and Swift follow-up photometric and spectroscopic observations of the source, finding that the transient had a peak luminosity of $L\simeq8\times10^{43}$~erg~s$^{-1}$ and a total integrated energy of $E\simeq1.7\times10^{50}$ ergs radiated over the $\sim5$ months of observations presented. The blackbody temperature of the transient remains roughly constant at $T\sim20,000$~K while the luminosity declines by nearly 1.5 orders of magnitude during this time, a drop that is most consistent with an exponential, $L\propto e^{-t/t_0}$ with $t_0\simeq39$~days. The source has broad Balmer lines in emission at all epochs as well as a broad He II feature emerging in later epochs. We compare the color and spectral evolution to both supernovae and normal AGN to show that {\name} does not resemble either type of object and conclude that a TDE is the most likely explanation for our observations. At $z=0.0436$, ASASSN-14ae is the lowest-redshift TDE candidate discovered at optical/UV wavelengths to date, and we estimate that ASAS-SN may discover $0.1 - 3$ of these events every year in the future.

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Thomas W. -S. Holoien, J. L. Prieto, D. Bersier, C. S. Kochanek, K. Z. Stanek, B. J. Shappee, D. Grupe, U. Basu, J. F. Beacom, J. Brimacombe, J. S. Brown, A. B. Davis, J. Jencson, G. Pojmanski, D. M. Szczygiel. 2014-05-06. ASASSN-14ae: A Tidal Disruption Event at 200 Mpc. https://doi.org/10.1093/mnras/stu1922

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