Sensitivity and figures of merit for dark energy supernova surveys

¹ Centre de Physique Théorique (“Centre de Physique Théorique” is UMR 6207 – “Unité Mixte de Recherche” of CNRS and of the Universities “de Provence”, “de la Méditerranée” and “du Sud Toulon-Var” – Laboratory affiliated to FRUMAM (FR 2291).) , Case 907, 13288 Marseille Cedex 9, France and Université de Provence, Marseille, France e-mail: virey@cpt.univ-mrs.fr
² Centre de Physique des Particules de Marseille, Case 907, 13288 Marseille Cedex 9, France

Received: 26 July 2006
Accepted: 22 December 2006

Abstract

Tracking the origin of the accelerating expansion of the Universe remains one of the most challenging research activities today. The final answer will depend on the precision and on the consistency of data from future surveys. The sensitivity of these surveys is related to the control of the cosmological parameters errors. We focus on supernova surveys in the light of the figure of merit defined by the Dark Energy Task Force. We estimate the impact of the level of systematic errors on the optimisation of SN surveys and emphasize their importance in deriving any sensitivity estimation. We discuss the lack of information of the DETF figure of merit to discriminate among dark energy models and compare the different representations that can help to distinguish ΛCDM from other theoretical models. We conclude that all representations should be controlled through combined analysis and consistency checks to avoid biases.