J/ApJ/877/81 The C3R2 survey: DR2 new spectroscopic redshifts (Masters+, 2019)
The Complete Calibration of the Color-Redshift Relation (C3R2) survey: analysis
and Data Release 2.
Masters D.C., Stern D.K., Cohen J.G., Capak P.L., Stanford S.A.,
Hernitschek N., Galametz A., Davidzon I., Rhodes J.D., Sanders D.,
Mobasher B., Castander F., Pruett K., Fotopoulou S.
<Astrophys. J., 877, 81 (2019)>
=2019ApJ...877...81M 2019ApJ...877...81M
ADC_Keywords: Galaxies, spectra; Redshifts; Surveys; Photometry, RI
Keywords: astronomical databases ; catalogs ; cosmology: observations ;
galaxies: distances and redshifts ; surveys
Abstract:
The Complete Calibration of the Color-Redshift Relation (C3R2) survey
is a multi-institution, multi-instrument survey that aims to map the
empirical relation of galaxy color to redshift to i∼24.5 (AB), thereby
providing a firm foundation for weak lensing cosmology with the
Stage IV dark energy missions Euclid and WFIRST. Here we present
3171 new spectroscopic redshifts obtained in the 2016B and 2017A
semesters with a combination of DEIMOS, LRIS, and MOSFIRE on the Keck
telescopes. The observations come from all of the Keck partners:
Caltech, NASA, the University of Hawaii, and the University of
California. Combined with the 1283 redshifts published in DR1, the
C3R2 survey has now obtained and published 4454 high-quality galaxy
redshifts. We discuss updates to the survey design and provide a
catalog of photometric and spectroscopic data. Initial tests of the
calibration method performance are given, indicating that the sample,
once completed and combined with extensive data collected by other
spectroscopic surveys, should allow us to meet the cosmology
requirements for Euclid, and make significant headway toward solving
the problem for WFIRST. We use the full spectroscopic sample to
demonstrate that galaxy brightness is weakly correlated with redshift
once a galaxy is localized in the Euclid or WFIRST color space, with
potentially important implications for the spectroscopy needed to
calibrate redshifts for faint WFIRST and LSST sources.
Description:
The spectroscopic observations were conducted from 2016 September to
2017 April with DEIMOS (0.5-10um), LRIS (0.32-1um) and MOSFIRE H-band
(1.45-1.8um) on the Keck telescopes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6.dat 178 4525 Redshift results
sp/* . 3977 Individual 1D spectra in FITS format
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See also:
II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007)
II/286 : VIRMOS deep imaging survey. VVDS-F02 catalog (VIRMOS team+, 2008)
III/334 : VISTA Deep Extragalactic Observations (VIDEO) (Jarvis+, 2013)
II/347 : KiDS-ESO-DR3 multi-band source catalog (de Jong+, 2017)
J/ApJS/172/70 : zCOSMOS-bright catalog (Lilly+, 2007)
J/ApJ/690/1236 : COSMOS photometric redshift catalog (Ilbert+, 2009)
J/A+A/544/A156 : UltraVISTA Catalogue Release DR1 (McCracken+, 2012)
J/ApJS/203/24 : Structural param. of galaxies in CANDELS (van der Wel+, 2012)
J/ApJS/206/10 : CANDELS multiwavelength catalog (Galametz+, 2013)
J/ApJ/795/165 : Line ratios in z∼2-3 gal. from KBSS-MOSFIRE (Steidel+, 2014)
J/ApJ/801/97 : GOODS-S & UDS stellar mass cat. from CANDELS (Santini+, 2015)
J/ApJS/224/24 : The COSMOS2015 catalog (Laigle+, 2016)
J/ApJ/841/111 : C3R2 survey: high-confidence z from DR1 (Masters+, 2017)
http://sites.google.com/view/c3r2-survey/home : C3R2 survey home page
http://koa.ipac.caltech.edu/Datasets/C3R2/ : C3R2 datasets on Keck
Observatory Archive
Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Field Field (COSMOS, VVDS, EGS, UDS or
"serendip") (1)
10- 16 I7 --- ID ? Identifier within field (none for
"serendip" sources)
18- 19 I2 h RAh [2/14] Hour of Right Ascension (J2000)
21- 22 I2 min RAm Minute of Right Ascension (J2000)
24- 29 F6.3 s RAs Second of Right Ascension (J2000)
31- 31 A1 --- DE- Sign of the Declination (J2000)
32- 33 I2 deg DEd Degree of Declination (J2000)
35- 36 I2 arcmin DEm Arcminute of Declination (J2000)
38- 42 F5.2 arcsec DEs Arcsecond of Declination (J2000)
44- 56 A13 --- Mask Mask name
58- 60 I3 --- Slit [0/125] Slit number on mask
62- 67 F6.3 mag imag [16.39/25.3]?=-1 CFHT/MegaCam i-band AB
magnitude
69- 74 F6.4 --- zspec [0/4.51] Measured spectroscopic redshift
76- 78 F3.1 --- Qual [3/4] Redshift quality flag (4=certain) (2)
80- 86 A7 --- Inst Keck spectrograph (DEIMOS, LRIS or MOSFIRE)
88-135 A48 --- FileName 1D spectra file name in subdirectory sp (3)
137-178 A42 --- FileName2 1D spectra file name in subdirectory sp (3)
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Note (1): All serendipitous detections are given the Field "serendip". While
some of these correspond to sources in existing photometric catalogs, we
have not applied IDs here. The coordinates we provide are correct
and can be cross-checked against the literature. The catalog contains a
small number of known duplicate observations.
Note (2): Quality flag from DR1 (Masters+ 2017, J/ApJ/841/111) as follows:
4.0 = Unambiguous redshift identified with multiple features or the
presence of the split [OII]λλ3726,3729 doublet;
3.5 = very high confidence but based on a single line detection;
3.0 = high confidence redshift with a low probability of an incorrect
identification.
Note (3): Sources with no value in "Filename" have not yet been
delivered to the Keck Observatory Archive (KOA). This includes the
serendipitous sources and a handful of LRIS-observed sources.
Some objects have 2 spectra, in b and r bands.
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History:
From electronic version of the journal for Table 6.
Spectra downloaded on: http://koa.ipac.caltech.edu/Datasets/C3R2/
References:
Masters et al. DR1 2017ApJ...841..111M 2017ApJ...841..111M Cat. J/ApJ/841/111
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 23-Nov-2020