UC Berkeley

In Part I we introduce the method and results of the Twin Supernova analysis.

This novel approach to Type Ia supernova standardization is currently only possible with

spectrophotometric timeseries observations from the Nearby Supernova Factory. As Chapters

1 through 4 will explore, we select an ideal subset of supernovae, find pairs whose features

match well in flux at all wavelengths and times, and test their dispersion in brightness.

The analysis is completed in a blinded fashion, ensuring that we are not tuning our results.

What we find is that twin supernovae do indeed have a small brightness dispersion.

Part II shows two additional analyses related to the standardization of Type Ia supernovae.

In Chapter 5 we present a check on the results of Bailey et al. [2009]. Literature supernovae

with spectra near maximum light were tested to see how well their magnitudes could be standardized

using the flux ratio method of Bailey et al [2009].

Chapter 6 shows a study with data from the Nearby Supernova Factory. Using only the

spectrophotometric observations near maximum light, we calculate monochromatic Hubble Diagram

residuals for each supernova. Those residuals are then corrected using a flux ratio, similar

to Bailey et al. [2009] to test the standardization possibilities using only near-maximum observations.