Sloan Digital Sky Survey and Spitzer Archival Observations of the Precursor of PSN J14021678+5426205 in M101
ATel #7082; P. Kelly (UCB), S. van Dyk (IPAC), O. Fox (UCB), A. V. Filippenko (UCB), R. Foley (UIUC)
on 16 Feb 2015; 07:25 UT
Credential Certification: Patrick Kelly (pkelly@astro.berkeley.edu)
Subjects: Infra-Red, Optical, Supernovae, Transient, Variables
We report a detection of the star at the reported position of PSN J14021678+5426205 (ATel #7063, #7069, #7070, #7072, #7079) in Sloan Digital Sky Survey (SDSS) images of M101 taken 7-10 March 2003 TAI. Within an aperture of r = 1.2" at the starâs position and after correcting for foreground extinction (Schlafly & Finkbeiner 2011, ApJ, 737, 103), we measure magnitudes in the Vega photometric system of u = 21.1 +/- 0.3 mag (22.1 AB); g = 21.6 +/- 0.3 mag (21.5 AB); r = 21.0 +/- 0.3 mag (21.2 AB); i = 20.6 +/- 0.3 mag (21.0 AB); and z = 21.9 +/- 0.9 mag (22.4 AB). These are roughly comparable to the UBVR magnitudes of the source from 2008 through mid-2012 before the current outburst as reported from measurements of Large Binocular Telescope (LBT) images of M101 (ATel #7069; Gerke et al. 2014).
A search of Spitzer IRAC images taken in 2004 (GTO-60; PI G. Rieke) yielded no detection at the transient position. We determined the following three-sigma upper limits in the Vega photometric system: ch1 (3.6 micron) = 19.0 mag; ch2 (4.5 micron) = 18.6 mag; ch3 (5.8 micron) = 17.1 mag; and ch4 (8 micron) = 16.6 mag. This may suggest that the precursor lacks a large mass of surrounding dust.
