@article{54621ceef2cd42a595d427b67bd6e4ee,
title = "Euclid preparation XX. the Complete Calibration of the Color-Redshift Relation survey: LBT observations and data release",
abstract = "The Complete Calibration of the Color-Redshift Relation survey (C3R2) is a spectroscopic program designed to empirically calibrate the galaxy color-redshift relation to the Euclid depth (IE = 24.5), a key ingredient for the success of Stage IV dark energy projects based on weak lensing cosmology. A spectroscopic calibration sample that is as representative as possible of the galaxies in the Euclid weak lensing sample is being collected, selecting galaxies from a self-organizing map (SOM) representation of the galaxy color space. Here, we present the results of a nearinfrared H- and K-band spectroscopic campaign carried out using the LUCI instruments at the LBT. For a total of 251 galaxies, we present new highly reliable redshifts in the 1.3 ≤ z ≤ 1.7 and 2 ≤ z ≤ 2.7 ranges. The newly-determined redshifts populate 49 SOM cells that previously contained no spectroscopic measurements and almost twice the occupation numbers of an additional 153 SOM cells. A final optical ground-based observational effort is needed to calibrate the missing cells, in particular in the redshift range 1.7 ≤ z ≤ 2.7, which lack spectroscopic calibration. In the end, Euclid itself will deliver telluric-free near-IR spectra that can complete the calibration.",
keywords = "Galaxies: distances and redshifts, catalogs, surveys",
author = "{Euclid Collaboration} and R. Saglia and {De Nicola}, S. and M. Fabricius and V. Guglielmo and J. Snigula and R. Z{\"o}ller and R. Bender and J. Heidt and D. Masters and D. Stern and S. Paltani and A. Amara and N. Auricchio and M. Baldi and C. Bodendorf and D. Bonino and E. Branchini and M. Brescia and J. Brinchmann and S. Camera and V. Capobianco and C. Carbone and J. Carretero and M. Castellano and S. Cavuoti and R. Cledassou and G. Congedo and Conselice, {C. J.} and L. Conversi and Y. Copin and L. Corcione and F. Courbin and M. Cropper and {Da Silva}, A. and H. Degaudenzi and M. Douspis and F. Dubath and Duncan, {C. A.J.} and X. Dupac and S. Dusini and S. Farrens and M. Frailis and E. Franceschi and S. Galeotta and B. Garilli and W. Gillard and B. Gillis and C. Giocoli and A. Grazian and R. Teyssier",
note = "Funding Information: The Euclid Consortium acknowledges the European Space Agency and a number of agencies and institutes that have supported the development of Euclid, in particular the Academy of Finland, the Agenzia Spaziale Italiana, the Belgian Science Policy, the Canadian Euclid Consortium, the French Centre National d{\textquoteright}Etudes Spatiales, the Deutsches Zentrum f{\"u}r Luft- und Raumfahrt, the Danish Space Research Institute, the Funda{\c c}{\~a}o para a Ci{\^e}ncia e a Tecnologia, the Ministerio de Ciencia e Innovaci{\'o}n, the National Aeronautics and Space Administration, the National Astronomical Observatory of Japan, the Netherlandse Onderzoekschool Voor Astronomie, the Norwegian Space Agency, the Romanian Space Agency, the State Secretariat for Education, Research and Innovation (SERI) at the Swiss Space Office (SSO), and the United Kingdom Space Agency. A complete and detailed list is available on the Euclid web site ( http://www.euclid-ec.org ). R.S., M.F., V.G., R.B. acknowledge support by the Deutsches Zentrum f{\"u}r Luft- und Raumfahrt (DLR) grant 50 QE 1101. The work of DS was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. We thank the staff of the LBT observatory for their support during the mask preparation and the execution of the observations. H. Hildebrandt is supported by a Heisenberg grant of the Deutsche Forschungsgemeinschaft (Hi 1495/5-1) as well as an ERC Consolidator Grant (No. 770935). Publisher Copyright: {\textcopyright} Euclid Collaboration et al. 2022.",
year = "2022",
month = aug,
doi = "10.1051/0004-6361/202243604",
language = "English (US)",
volume = "664",
journal = "Astronomy and Astrophysics",
issn = "0004-6361",
publisher = "EDP Sciences",
}