The VIMOS VLT Deep Survey: The K-band follow-up in the 0226-04 field

TL;DR

This paper presents an extended Ks-band survey in the 0226-04 field of the VVDS, providing a large, deep, multiwavelength catalog that improves photometric redshift accuracy and offers valuable data for galaxy evolution studies.

Contribution

It introduces a new, larger Ks-band survey with improved photometric redshift accuracy, expanding the existing VVDS dataset with publicly available, multiwavelength galaxy catalogues.

Findings

Catalog contains ~52,000 sources with 90% completeness at K_Vega=20.5 mag.

Use of K-band magnitudes reduces catastrophic photometric redshift errors.

Galaxy counts and angular correlation functions are consistent with previous studies.

Abstract

AIMS. We present a new Ks-band survey that represents a significant extension to the previous wide-field Ks-band imaging survey within the 0226-04 field of the VIMOS-VLT deep survey (VVDS). The new data add ~ 458 arcmin^2 to the previous imaging program, thus allowing us to cover a total contiguous area of ~ 600 arcmin^2 within this field. METHODS. Sources are identified both directly on the final K-band mosaic image and on the corresponding, deep chi^2-g'r'i' image from the CFHT Legacy Survey in order to reduce contamination while ensuring us the compilation of a truly K-selected catalogue down to the completeness limit of the Ks-band. The newly determined Ks-band magnitudes are used in combination with the ancillary multiwavelength data for the determination of accurate photometric redshifts. RESULTS. The final catalogue totals ~ 52000 sources, out of which ~ 4400 have a spectroscopic redshift from the VVDS first epoch survey. The catalogue is 90% complete down to K_Vega = 20.5 mag. We present K_s-band galaxy counts and angular correlation function measurements down to such magnitude limit. Our results are in good agreement with previously published work. We show that the use of K magnitudes in the determination of photometric redshifts significantly lowers the incidence of catastrophic errors. The data presented in this paper are publicly available through the CENCOS database.