ASAS-SN Recent Limits on Brightness of PSN J14021678+5426205 in M101

ATel #7063; K. Z. Stanek, A. B. Danilet, T. W.-S. Holoien, C. S. Kochanek, G. Simonian, U. Basu, N. Goss, J. F. Beacom (Ohio State), B. J. Shappee (Hubble Fellow, Carnegie Obsrvatories), J. L. Prieto (Diego Portales; MAS), D. Bersier (LJMU), J. Brimacombe (Coral Towers Observatory), Subo Dong (KIAA-PKU), E. Falco (CfA), M. Wagner (LBTO), P. R. Wozniak (LANL), D. Szczygiel, G. Pojmanski (Warsaw University Observatory)
on 14 Feb 2015; 02:34 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Krzysztof Stanek (stanek.32@osu.edu)

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PSN J14021678+5426205 in M101 was detected on UT 2015-02-10.904 at an unfiltered magnitude of 16.5, and confirmed on 2015-02-13.540 at around mag 16.7. The position of PSN J14021678+5426205 was observed on multiple epoch by the 14-cm ASAS-SN quadruple "Brutus" telescope, with no V-band (image-subtraction based) detection of a new source during any epoch, including

 
 UT_date         V    
2015-02-11.54  >17.24   
2015-02-12.49  >17.26   

These upper limits, obtained from ASAS-SN V-band data, combined with no obvious brightening of the source in unfiltered observations described above, make it unlikely that PSN J14021678+5426205 is a bona fide supernova. Given the distance to M101 (6.4 Mpc; Shappee & Stanek 2011), the absolute magnitude of PSN J14021678+5426205 is about -12.

We thank LCOGT and its staff for their continued support of ASAS-SN. ASAS-SN is supported in part by Mt. Cuba Astronomical Foundation.