Type Ia Supernova Intrinsic Magnitude Dispersion and the Fitting of Cosmological Parameters

Understand

I present an analysis for fitting cosmological parameters from a Hubble Diagram of a standard candle with unknown intrinsic magnitude dispersion.

• The dispersion is determined from the data themselves, simultaneously with the cosmological parameters.
• This contrasts with the strategies used to date.
• The advantages of the presented analysis are that it is done in a single fit (it is not iterative), it provides a statistically founded and unbiased estimate of the intrinsic dispersion, and its cosmological-parameter uncertainties account for the intrinsic dispersion uncertainty.