Tracing the sound horizon scale with photometric redshift surveys

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©2010 RAS ©2010 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.We propose a new method for the extraction cosmological parameters using the baryon acoustic oscillation (BAO) scale as a standard ruler in deep galaxy surveys with photometric determination of redshifts. The method consists in a simple empirical parametric fit to the angular two-point correlation function ω(θ). It is parametrized as a power law to describe the continuum and as a Gaussian to describe the BAO bump. The location of the Gaussian is used as the basis for the measurement of the sound horizon scale. This method, although simple, actually provides a robust estimation, since the inclusion of the power law and the use of the Gaussian remove the shifts which affect the local maximum. We discuss the effects of projection bias, non-linearities, redshift space distortions and photo-z precision and apply our method to a mock catalogue of the Dark Energy Survey, built upon a large N-body simulation provided by the MICE collaboration. We discuss the main systematic errors associated with our method and show that they are dominated by the photo-z uncertaintyWe thank the Spanish Ministry of Science and Innovation (MICINN) for funding support through grants AYA2009- 13936-C06-01, AYA2009-13936-C06-03, AYA2009-13936-C06- 04, AYA2009-13936-C06-06 and through the Consolider Ingenio- 2010 programme, under project CSD2007-0006