SALT: a spectral adaptive light curve template for type Ia supernovae
Abstract
We present a new method to parameterize type Ia Supernovae (SN Ia) multi-color light curves. The method was developed in order to analyze the large number of SN Ia multi-color light curves measured in current high-redshift projects. The technique is based on empirically modeling SN Ia luminosity variations as a function of phase, wavelength, a shape parameter, and a color parameter. The model is trained with a sample of well-measured nearby SN Ia and then tested with an independent set of supernovae by building an optimal luminosity distance estimator that combines the supernova rest-frame luminosity, shape parameter, and color reconstructed with the model. The distances we measure using B- and V-band data show a dispersion around the Hubble line comparable or lower than obtained with other methods. With this model, we are able to measure distances using U- and B-band data with a dispersion of 0.16±0.05 around the Hubble line.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- December 2005
- DOI:
- 10.1051/0004-6361:20053025
- arXiv:
- arXiv:astro-ph/0506583
- Bibcode:
- 2005A&A...443..781G
- Keywords:
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- supernovae: general;
- cosmology: observations;
- Astrophysics
- E-Print:
- Accepted in A&