AAVSO: American Association of Variable Star Observers
Login

BVRI Photometry of SN 2011fe in M101

Volume 40 number 2 (2012)

Download this article (pdf)

Michael W. Richmond
Physics Department, Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, NY, 14623; mwrsps@rit.edu
Horace A. Smith
Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824; smith@pa.msu.edu

Abstract

We present BVRI photometry of Supernova 2011fe in M101, starting 2.9 days after the explosion and ending 179 days later. The light curves and color evolution show that SN 2011fe belongs to the "normal" subset of type Ia supernovae, with a decline parameter Delta m15(B) = 1.21 ± 0.03 mag. After correcting for the small amount of extinction in the line of sight, and adopting a distance modulus of (m-M) = 29.10 mag to M101, we derive absolute magnitudes MB = -19.21, MV = -19.19, MR = -19.18, and MI = -18.94. We compare the voluminous record of visual measurements of this event to our CCD photometry and find evidence for a systematic difference which depends on color.