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arXiv · 0802.1012

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

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.

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S. Temporin, A. Iovino, M. Bolzonella, H. J. McCracken, M. Scodeggio, B. Garilli, D. Bottini, V. Le Brun, O. Le Fevre, D. Maccagni, J. P. Picat, R. Scaramella, L. Tresse, G. Vettolani, A. Zanichelli, C. Adami, S. Arnouts, S. Bardelli, A. Cappi, S. Charlot, P. Ciliegi, T. Contini, O. Cucciati, S. Foucaud, P. Franzetti, I. Gavignaud, L. Guzzo, O. Ilbert, B. Marano, C. Marinoni, A. Mazure, B. Meneux, R. Merighi, S. Paltani, R. Pello, A. Pollo, L. Pozzetti, M. Radovich, D. Vergani, G. Zamorani, E. Zucca, M. Bondi, A. Bongiorno, J. Brinchmann, S. de la Torre, F. Lamareille, Y. Mellier, C. J. Walcher. 2008-02-07. The VIMOS VLT Deep Survey: The K-band follow-up in the 0226-04 field. https://doi.org/10.1051/0004-6361:20078526

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