D. M. Szczygiel, J. L. Prieto, C. S. Kochanek, K. Z. Stanek, T. A. Thompson, J. F. Beacom, P. M. Garnavich, C. E. Woodward
We obtained late-time optical and near-IR imaging of SN 2008S with the Large
Binocular Telescope (LBT), near-IR data with the Hubble Space Telescope (HST),
and mid-IR data with the Spitzer Space Telescope (SST). We find that (1) it is
again invisible at optical (UBVR) wavelengths to magnitude limits of
approximately 25 mag, (2) while detected in the near-IR (H) at approximately
24.8 mag, it is fading rapidly, and (3) it is still brighter than the
progenitor at 3.6 and 4.5 microns in the mid-IR with a slow, steady decline.
The IR detections in December 2010 are consistent with dust emission at a
blackbody temperature of T ~ 640 K and a total luminosity of L ~ 200000 Lsun,
much higher than the L ~ 40000 Lsun luminosity of the obscured progenitor star.
The local environment also shows no evidence for massive (M >= 10 Msun) stars
in the vicinity of the transient, consistent with the progenitor being a
massive AGB star.
View original:
http://arxiv.org/abs/1202.0279
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