A1 Journal article (refereed)
Euclid preparation : XX. The Complete Calibration of the Color–Redshift Relation survey : LBT observations and data release (2022)


Euclid Collaboration. (2022). Euclid preparation : XX. The Complete Calibration of the Color–Redshift Relation survey : LBT observations and data release. Astronomy and Astrophysics, 664, Article A196. https://doi.org/10.1051/0004-6361/202243604


JYU authors or editors


Publication details

All authors or editorsEuclid Collaboration

Journal or seriesAstronomy and Astrophysics

ISSN0004-6361

eISSN1432-0746

Publication year2022

Publication date30/08/2022

Volume664

Article numberA196

PublisherEDP Sciences

Publication countryFrance

Publication languageEnglish

DOIhttps://doi.org/10.1051/0004-6361/202243604

Publication open accessOpenly available

Publication channel open accessPartially open access channel

Publication is parallel published (JYX)https://jyx.jyu.fi/handle/123456789/83651


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 near-infrared 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.


Keywordscosmologydark energygalaxiesspectroscopynear infrared spectroscopy


Contributing organizations


Ministry reportingYes

Reporting Year2022

JUFO rating2


Last updated on 2024-15-06 at 20:26