The VIRMOS deep imaging survey II: CFH12K BVRI optical data for the 0226-04 deep field

TL;DR

This paper details the creation and validation of a deep, multi-colour optical catalog covering 1.2 square degrees, providing reliable photometric and astrometric data for faint galaxies to support studies of galaxy evolution.

Contribution

It presents a comprehensive, bias-free photometric catalog with high accuracy and completeness, suitable for galaxy evolution research and follow-up spectroscopy.

Findings

Catalog contains 90,729 sources with reliable photometry up to IAB<24.0.

Astrometric uncertainties are less than 0.38" for 68% of sources.

Photometric errors are estimated to be within 10% for the I-band sample.

Abstract

(abridged) In this paper we describe in detail the reduction, preparation and reliability of the photometric catalogues which comprise the 1.2 deg^2 CFH12K-VIRMOS deep field. The survey reaches a limiting magnitude of BAB~26.5, VAB~26.2, RAB~25.9 IAB~25.0 and contains 90,729 extended sources in the magnitude range 18.0<IAB<24.0. We demonstrate our catalogues are free from systematic biases and are complete and reliable down these limits. We estimate that the upper limit on bin-to-bin systematic photometric errors for the I- limited sample is ~10% in this magnitude range. We estimate that 68% of the catalogues sources have absolute per co-ordinate astrometric uncertainties less than ~0.38" and ~0.32" (alpha,delta). Our internal (filter-to-filter) per co-ordinate astrometric uncertainties are 0.08" and 0.08" (alpha,delta). We quantify the completeness of our survey in the joint space defined by object total magnitude and peak surface brightness. Finally, we present numerous comparisons between our catalogues and published literature data: galaxy and star counts, galaxy and stellar colours, and the clustering of both point-like and extended populations. In all cases our measurements are in excellent agreement with literature data to IAB<24.0. This combination of depth and areal coverage makes this multi-colour catalogue a solid foundation to select galaxies for follow-up spectroscopy with VIMOS on the ESO-VLT and a unique database to study the formation and evolution of the faint galaxy population to z~1 and beyond.