Optical and Near-Infrared Photometry of the Type Ia Supernova 2000E in NGC 6951

摘要

We present optical (UBVRI) and near-infrared (JHK) photometry, along with optical spectra, of the Type Ia supernova SN 2000E in the spiral galaxy NGC 6951. It was discovered by the staff of the Teramo Observatory during the monitoring of the SN 1999el. The observations span a time interval of 234 days in the optical and 134 days in the near-infrared (starting ~16 and ~7 days before maximum B light, respectively). Optical spectra are available from 6 days before maximum B light to 122 days after it. The photometric behavior of SN 2000E is remarkably similar to that of SN 1991T and SN 1992bc: it exhibits a Δm15(B) = 0.94 mag, thus being classifiable as a slow-declining Type Ia supernova (SN) and showing the distinctive features of such a class of objects both in the visible and in the near-infrared. Spectroscopically, SN 2000E appears as a "normal" Type Ia SN, like SN 1990N. We could constrain reddening [E(B-V) ~ 0.5 mag] and distance (μ0 ~ 32.14 mag) using a number of different methods. The bolometric luminosity curve of SN 2000E, which displays a bump at the epoch of the secondary near-infrared peak, allows a determination of the 56Ni mass, amounting to 0.9 M☉.