Euclid preparation: VIII. The Complete Calibration of the Colour-Redshift Relation survey: VLT/KMOS observations and data release
Abstract
The Complete Calibration of the Colour-Redshift Relation survey (C3R2) is a spectroscopic effort involving ESO and Keck facilities designed to empirically calibrate the galaxy colour-redshift relation - P(z|C) to the Euclid depth (i_AB=24.5) and is intimately linked to upcoming Stage IV dark energy missions based on weak lensing cosmology. The aim is to build a spectroscopic calibration sample that is as representative as possible of the galaxies of the Euclid weak lensing sample. In order to minimise the number of spectroscopic observations to fill the gaps in current knowledge of the P(z|C), self-organising map (SOM) representations of the galaxy colour space have been constructed. Here we present the first results of an ESO@ VLT Large Programme approved in the context of C3R2, which makes use of the two VLT optical and near-infrared multi-object spectrographs, FORS2 and KMOS. This paper focuses on high-quality spectroscopic redshifts of high-z galaxies observed with the KMOS spectrograph in the H- and K-bands. A total of 424 highly-reliable z are measured in the 1.3<=z<=2.5 range, with total success rates of 60.7% in the H-band and 32.8% in the K-band. The newly determined z fill 55% of high and 35% of lower priority empty SOM grid cells. We measured Halpha fluxes in a 1."2 radius aperture from the spectra of the spectroscopically confirmed galaxies and converted them into star formation rates. In addition, we performed an SED fitting analysis on the same sample in order to derive stellar masses, E(B-V), total magnitudes, and SFRs. We combine the results obtained from the spectra with those derived via SED fitting, and we show that the spectroscopic failures come from either weakly star-forming galaxies (at z<1.7, i.e. in the H-band) or low S/N spectra (in the K-band) of z>2 galaxies.
Cite
@article{arxiv.2007.02631,
title = {Euclid preparation: VIII. The Complete Calibration of the Colour-Redshift Relation survey: VLT/KMOS observations and data release},
author = {Euclid Collaboration and V. Guglielmo and R. Saglia and F. J. Castander and A. Galametz and S. Paltani and R. Bender and M. Bolzonella and P. Capak and O. Ilbert and D. C. Masters and D. Stern and S. Andreon and N. Auricchio and A. Balaguera-Antolínez and M. Baldi and S. Bardelli and A. Biviano and C. Bodendorf and D. Bonino and E. Bozzo and E. Branchini and S. Brau-Nogue and M. Brescia and C. Burigana and R. A. Cabanac and S. Camera and V. Capobianco and A. Cappi and C. Carbone and J. Carretero and C. S. Carvalho and R. Casas and S. Casas and M. Castellano and G. Castignani and S. Cavuoti and A. Cimatti and R. Cledassou and C. Colodro-Conde and G. Congedo and C. J. Conselice and L. Conversi and Y. Copin and L. Corcione and A. Costille and J. Coupon and H. M. Courtois and M. Cropper and A. Da Silva and S. de la Torre and D. Di Ferdinando and F. Dubath and C. A. J. Duncan and X. Dupac and S. Dusini and M. Fabricius and S. Farrens and P. G. Ferreira and S. Fotopoulou and M. Frailis and E. Franceschi and M. Fumana and S. Galeotta and B. Garilli and B. Gillis and C. Giocoli and G. Gozaliasl and J. Graciá-Carpio and F. Grupp and L. Guzzo and H. Hildebrandt and H. Hoekstra and F. Hormuth and H. Israel and K. Jahnke and E. Keihanen and S. Kermiche and M. Kilbinger and C. C. Kirkpatrick and T. Kitching and B. Kubik and M. Kunz and H. Kurki-Suonio and R. Laureijs and S. Ligori and P. B. Lilje and I. Lloro and D. Maino and E. Maiorano and C. Maraston and O. Marggraf and N. Martinet and F. Marulli and R. Massey and S. Maurogordato and E. Medinaceli and S. Mei and M. Meneghetti and R. Benton Metcalf and G. Meylan and M. Moresco and L. Moscardini and E. Munari and R. Nakajima and C. Neissner and S. Niemi and A. A. Nucita and C. Padilla and F. Pasian and L. Patrizii and A. Pocino and M. Poncet and L. Pozzetti and F. Raison and A. Renzi and J. Rhodes and G. Riccio and E. Romelli and M. Roncarelli and E. Rossetti and A. G. Sanchez and D. Sapone and P. Schneider and V. Scottez and A. Secroun and S. Serrano and C. Sirignano and G. Sirri and F. Sureau and P. Tallada-Crespi and D. Tavagnacco and A. N. Taylor and M. Tenti and I. Tereno and R. Toledo-Moreo and F. Torradeflot and A. Tramacere and L. Valenziano and T. Vassallo and Y. Wang and N. Welikala and M. Wetzstein and L. Whittaker and A. Zacchei and G. Zamorani and J. Zoubian and E. Zucca},
journal= {arXiv preprint arXiv:2007.02631},
year = {2021}
}
Comments
21 pages, 12 figures