Modeling the Lightcurves of Type Ia Supernovae

Abstract

In order to investigate non-uniformity in the luminosity evolution of Type Ia supernovae, we fit the lightcurves with a multi-parameter empirical model. The model provides a quantitative method of analyzing the lightcurves of Type I supernovae and a convenient and continuous representation of the photometric data. Using photometry of the well-observed event SN 1994D we demonstrate the application of the model and construct a bolometric lightcurve. The rise time of the bolometric light curve can be estimated and compared to current theoretical models. By applying this model to a large number of SN Ia lightcurves in various filters, we can explore the variations among individual events and derive systematic correlations. We find that the initial decline rate after maximum light correlates with the decline rate at late phases. Such correlations can be used to constrain theoretical models.