Supernova CCD Photometry: Reduction Methods and Light Curves
Session 37 -- Supernovae and Their Remnants
Display presentation, Wednesday, June 14, 1995, 9:20am - 6:30pm

## [37.01] Supernova CCD Photometry: Reduction Methods and Light Curves

C.~Y.~Peng, S.~D.~Van Dyk, R.~R.~Treffers, Y.~B.~Paik, A.~V.~Filippenko (UC Berkeley), M.~W.~Richmond (Princeton)

\noindent We present photometry of supernovae, particularly at late times, from broad-band CCD images taken with the 0.5-m and 0.76-m robotic telescopes at Leuschner Observatory (near the UC Berkeley campus) and the Nickel 1-m reflector at Lick Observatory. Dedicated to long-term photometry of supernovae and other ephemeral or variable objects, the 0.5-m telescope is the companion of the 0.76-m reflector, which is used for the Leuschner Observatory Supernova Search (LOSS). We present an analysis and comparison of the template subtraction'' and rotation subtraction'' techniques for removing galaxy background light. We find these methods to be superior to simple aperture photometry, which is generally inadequate for deriving accurate light curves of supernovae, especially at late times. We also consider the viability of using template'' images having pixel scales that differ from those of the supernova images. Using these methods, we present detailed multiband light curves of SNe 1992H, 1993R, 1993Z, 1994D, and 1994I.