* Astronomy

Title: Discovery and Observations of ASASSN-13db, an EXor Accretion Event on a Low-Mass T Tauri Star
Author: Thomas W.-S. Holoien, Jose L. Prieto, Krzysztof Z. Stanek, Christopher S. Kochanek, B. J. Shappee, Z. Zhu, A. Sicilia-Aguilar, D. Grupe, K. Croxall, J. Adams, J. D. Simon, N. Morell S. M. McGraw, R. M. Wagner, U. Basu, J. F.Beacom, D. Bersier, J. Brimacombe, J. Jencson, G. Pojmanski, S. G. Starrfield, D. M. Szczygie, C. E. Woodward

We discuss ASASSN-13db, an EXor accretion event on the young stellar object (YSO) SDSS J051011.01032826.2 (hereafter SDSSJ0510) discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN). Using archival photometric data of SDSSJ0510 we construct a pre-outburst spectral energy distribution (SED) and find that it is consistent with a low-mass class II YSO near the Orion star forming region (d420 pc). We present follow-up photometric and spectroscopic observations of the source after the V3.7 mag outburst that began in September 2013. These data indicate an increase in temperature and luminosity consistent with an accretion rate of 107 solar masses yr1, three-to-five orders of magnitude greater than in quiescence. Spectroscopic observations show a forest of narrow emission lines dominated by neutral metallic lines from Fe I and some low-ionization lines. The properties of ASASSN-13db are similar to those of the EXor prototype EX~Lupi in late 2008 during its strongest observed outburst.

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