Correlated Supernova Systematics and Ground Based Surveys

TL;DR

This paper examines how wavelength-dependent systematic uncertainties in supernova measurements affect dark energy constraints, highlighting that extending wavelength sensitivity can significantly improve survey performance.

Contribution

It introduces a global correlation model for supernova systematics based on wavelength dependence and assesses its impact on ground-based surveys like DES and LSST.

Findings

Wavelength-dependent systematics can significantly influence dark energy constraints.

Extending wavelength sensitivity to 1.05 microns can double the dark energy figure of merit.

Global correlation models differ from local-redshift models in their impact on survey results.

Abstract

Supernova distances provide a direct probe of cosmic acceleration, constraining dark energy. This leverage increases with survey redshift depth at a rate bounded by the systematic uncertainties. We investigate the impact of a wavelength-dependent, global correlation model of systematics in comparison to the standard local-redshift correlation model. This can arise from subclass uncertainties as features in the supernova spectrum redshift out of the observer photometric filters or spectral range. We explore the impact of such a systematic on ground-based supernova surveys such as Dark Energy Survey and LSST, finding distinctive implications. Extending the wavelength sensitivity to 1.05 microns through "extreme red" CCDs can improve the dark energy figure of merit by up to a factor 2.