Optical and Infrared Photometry of SN 2005df

TL;DR

This paper provides detailed optical and infrared photometry of the Type Ia supernova 2005df, confirming its unreddened status and contributing to distance measurements of its host galaxy through Cepheid observations.

Contribution

It offers new multi-band photometry data and spectropolarimetry for SN 2005df, enhancing understanding of its properties and host galaxy distance.

Findings

SN 2005df is unreddened in its host galaxy.

Photometry matches previous measurements after corrections.

Spectropolarimetry data obtained for the supernova.

Abstract

We present optical BVRI and near-infrared YJHK_s photometry of the normal Type Ia supernova 2005df, obtained with the CTIO 1.3-m and 0.9-m telescopes. The B- and V-band photometry, S-corrected to the filter prescriptions of Bessell(1990), matches the corresponding photometry from the ANU published by Milne et al. (2010). The R-band photometry from CTIO and ANU matches well without any corrections. A combination of V-band and near-IR photometry shows that SN 2005df is unreddened in its host galaxy. Spectropolarimetry of this supernova was obtained with the VLT, and the distance to the host galaxy is being determined from observations of Cepheids using the Hubble Space Telescope.