V/161 DESI DR1 redshift catalog (DESI Col.+ 2025)
Data Release 1 of the Dark Energy Spectroscopic Instrument.
DESI Collaboration et al.
=2025arXiv250314745D 2025arXiv250314745D
=2025yCat.5161....0D 2025yCat.5161....0D
ADC_Keywords: Photometry, ugriz; Surveys; Spectra, optical; Redshifts;
Proper motions; Parallaxes, trigonometric; Morphology
Keywords: Cosmology and Nongalactic Astrophysics
Abstract:
In 2021 May the Dark Energy Spectroscopic Instrument (DESI)
collaboration began a 5-year spectroscopic redshift survey to produce
a detailed map of the evolving three-dimensional structure of the
universe between z=0 and z∼4. DESI's principle scientific objectives
are to place precise constraints on the equation of state of dark
energy, the gravitationally driven growth of large-scale structure,
and the sum of the neutrino masses, and to explore the observational
signatures of primordial inflation. We present DESI Data Release 1
(DR1), which consists of all data acquired during the first 13 months
of the DESI main survey, as well as a uniform reprocessing of the DESI
Survey Validation data which was previously made public in the DESI
Early Data Release. The DR1 main survey includes high-confidence
redshifts for 18.7M objects, of which 13.1M are spectroscopically
classified as galaxies, 1.6M as quasars, and 4M as stars, making DR1
the largest sample of extragalactic redshifts ever assembled. We
summarize the DR1 observations, the spectroscopic data-reduction
pipeline and data products, large-scale structure catalogs,
value-added catalogs, and describe how to access and interact with the
data. In addition to fulfilling its core cosmological objectives with
unprecedented precision, we expect DR1 to enable a wide range of
transformational astrophysical studies and discoveries.
Description:
In 2025arXiv250314745D 2025arXiv250314745D, we present the Dark Energy Spectroscopic
Instrument (DESI) Data Release 1 (DR1), which includes all the data
obtained by DESI during its first 13 months of science operations
(2021 May 14 through 2022 June 13), including data presented in the
Early Data Release (EDR; 2024AJ....168...58D 2024AJ....168...58D) as well as a uniform
reprocessing of all the five-month survey validation (SV) data.
DESI is capable of observing 5000 objects simultaneously using
10 petals of 500 fibers each over an 8deg2 field-of-view focal
plane. These fibers send light to 10 corresponding spectrographs with
three arms, or cameras, sensitive to a different portion of the
3600-9800Å observed-frame wavelength range. The three cameras are
sensitive to blue, red, and near-infrared light, and are denoted B, R,
and Z, respectively.
The redshift catalog (zcatalog) v1 presented here combine redshifts
and classifications from individual redrock files with the
corresponding target and observing metadata.
Acknowledging DESI DR1 in publications:
When DESI data are used, the appropriate credit is required by citing
[DESI Collaboration et al. (2025)](https://arxiv.org/abs/2503.14745),
"Data Release 1 of the Dark Energy Spectroscopic Instrument" and by
including the acknowledgements text provided at
https://data.desi.lbl.gov/doc/acknowledgments/ :
This research used data obtained with the Dark Energy Spectroscopic
Instrument (DESI). DESI construction and operations is managed by the
Lawrence Berkeley National Laboratory. This material is based upon
work supported by the U.S. Department of Energy, Office of Science,
Office of High-Energy Physics, under Contract No. DE-AC02-05CH11231,
and by the National Energy Research Scientific Computing Center, a DOE
Office of Science User Facility under the same contract. Additional
support for DESI was provided by the U.S. National Science Foundation
(NSF), Division of Astronomical Sciences under Contract No. AST-0950945
to the NSF's National Optical-Infrared Astronomy Research Laboratory;
the Science and Technology Facilities Council of the United Kingdom;
the Gordon and Betty Moore Foundation; the Heising-Simons Foundation;
the French Alternative Energies and Atomic Energy Commission (CEA);
the National Council of Humanities, Science and Technology of Mexico
(CONAHCYT); the Ministry of Science and Innovation of Spain (MICINN),
and by the DESI Member Institutions:
www.desi.lbl.gov/collaborating-institutions. The DESI collaboration is
honored to be permitted to conduct scientific research on I'oligam
Du'ag (Kitt Peak), a mountain with particular significance to the
Tohono O'odham Nation. Any opinions, findings, and conclusions or
recommendations expressed in this material are those of the author(s)
and do not necessarily reflect the views of the U.S. National Science
Foundation, the U.S. Department of Energy, or any of the listed
funding agencies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
zcatdr1.sam 764 1000 DESI DR1 redshift catalog (ZCATALOG), sample
output (on a total of 28,425,963 sources)
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/356 : Gaia DR3 Part 2. Extra-galactic (Gaia Collaboration, 2022)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
I/358 : Gaia DR3 Part 4. Variability (Gaia Collaboration, 2022)
I/359 : Gaia DR3 Part 5. Solar System (Gaia Collaboration, 2022)
I/360 : Gaia DR3 Part 6. Performance verification (Gaia Collaboration, 2022)
VII/292 : DESI Legacy Imaging Surveys DR8 photometric redshifts (Duncan, 2022)
J/ApJS/132/37 : Spectroscopy of Southern warm IR galaxies (Kewley+, 2001)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/A+A/622/A103 : Python Code Investigating GALaxy Emission (Boquien+, 2019)
J/MNRAS/505/5978 : Gaia EDR3 view on Gal. globular clusters (Vasiliev+, 2021)
J/A+A/660/A29 : Sp.-phot. distances of ∼ 300000 SEGUE stars (Thomas+, 2022)
J/ApJ/944/1 : DESI observations of the Andromeda galaxy (Dey+, 2023)
J/MNRAS/525/1106 : DESI Peculiar Velocity survey (Saulder+, 2023)
J/ApJS/269/3 : Siena Galaxy Atlas 2020 (SGA-2020) (Moustakas+, 2023)
J/ApJS/269/27 : DESI z≳5 quasar survey. I. New z∼4.7-6.6 QSOs (Yang+, 2023)
J/A+A/691/A308 : Physical properties of DESI galaxies (Siudek+, 2024)
J/ApJS/273/19 : Elemental abundances from DESI EDR spectra (Zhang+, 2024)
http://data.desi.lbl.gov/doc : DESI documentation homepage
http://desidatamodel.readthedocs.io/en/latest/DESI_SPECTRO_REDUX/SPECPROD/
zcatalog/v1/zpix-SURVEY-PROGRAM.html : zcatalog v1 datamodel description
http://www.legacysurvey.org/ : DESI Legacy Imaging Surveys homepage
Byte-by-byte Description of file: zcatdr1.sam
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- TargetID [-826479526/2882315850818256979]
Unique DESI target ID (TARGETID)
21- 36 F16.12 deg RAdeg Barycentric Right Ascension in ICRS
(TARGET_RA)
38- 53 F16.12 deg DEdeg [-32/85] Barycentric Declination in
ICRS (TARGET_DEC)
55- 61 A7 --- Survey Survey name (SURVEY)
63- 68 A6 --- Prog DESI program type - BRIGHT; DARK;
BACKUP; OTHER (PROGRAM)
70- 74 I5 --- Healpix [0/49151] HEALPixel containing this
location at NSIDE=64 in the NESTED
scheme (HEALPIX)
76- 91 E16.9 --- z [-0.0044/7] Redshift measured by
Redrock (Z)
93-107 E15.9 --- e_z [0/0.03] Redshift error from redrock
(ZERR)
109-112 I4 --- ZWARN [0/2695] Redshift warning bitmask from
Redrock (0=good)
114-127 E14.9 --- Chi2 [2/9e99] Best fit chi squared (CHI2)
129-143 E15.9 --- COEFF0 Redrock template coefficients 0
(COEFF_0)
145-159 E15.9 --- COEFF1 Redrock template coefficients 1
(COEFF_1)
161-175 E15.9 --- COEFF2 Redrock template coefficients 2
(COEFF_2)
177-191 E15.9 --- COEFF3 Redrock template coefficients 3
(COEFF_3)
193-207 E15.9 --- COEFF4 Redrock template coefficients 4
(COEFF_4)
209-223 E15.9 --- COEFF5 Redrock template coefficients 5
(COEFF_5)
225-239 E15.9 --- COEFF6 Redrock template coefficients 6
(COEFF_6)
241-255 E15.9 --- COEFF7 Redrock template coefficients 7
(COEFF_7)
257-271 E15.9 --- COEFF8 Redrock template coefficients 8
(COEFF_8)
273-287 E15.9 --- COEFF9 Redrock template coefficients 9
(COEFF_9)
289-292 I4 --- Npix [0/7933] Number of unmasked pixels
contributing to the Redrock fit
(NPIXELS)
294-299 A6 --- OType Spectral type of Redrock best fit
template (SPECTYPE) (1)
301-303 A3 --- SubType Spectral subtype (SUBTYPE)
305-318 E14.9 --- delChi2 [0/3.6e7] Chi2 difference between
first- and second-best redrock
template fits (DELTACHI2)
320-329 I10 --- COADD_FIBER [0/1098907648] Bitwise-AND of input
FIBERSTATUS (COADD_FIBERSTATUS) (2)
331-339 F9.3 mas/yr pmRA [-4513/3980] Reference catalog proper
motion in the RA direction (PMRA)
341-349 F9.3 mas/yr pmDE [-3438/2106] Reference catalog proper
motion in the Dec direction (PMDEC)
351-359 F9.4 yr RefEp [0/2021.97] Reference catalog
reference epoch
(e.g.; 2015.5 for GaiaDR2) (REF_EPOCH)
361-363 A3 --- Type Object type: TGT; SKY; NON; BAD
(OBJTYPE)
365-367 I3 --- Obs [0/575] Flag the target to be observed
in graytime (OBSCONDITIONS)
369-372 I4 --- Release [-1/9012] Legacy Surveys (LS) Release
(RELEASE) (3)
374-381 A8 --- BrickName Brick name from tractor input
(BRICKNAME)
383-388 I6 --- BrickID [0/785162] Brick ID from tractor input
(BRICKID)
390-394 I5 --- ObjID [-1/31798] OBJID
(unique to brick; but not to file)
(BRICK_OBJID)
396-399 A4 --- Morph Morphological Model type (MORPHTYPE) (4)
401-408 F8.6 mag EBV [0/4] Galactic extinction E(B-V)
reddening from
Schlegel+ 1998ApJ...500..525S 1998ApJ...500..525S
410-421 E12.6 3.63uJy Fg [-1771/70844] Legacy Survey (LS) flux
from tractor input (g),
in nanomaggy units (FLUX_G)
423-434 E12.6 3.63uJy Fr [-249/149823] LS flux from tractor
input (r), in nanomaggy units (FLUX_R)
436-447 E12.6 3.63uJy Fz [-13229/193772] LS flux from tractor
input (z), in nanomaggy units (FLUX_Z)
449-460 E12.6 3.63uJy F3.4 [-224146/9016309] WISE flux in W1
(3.4um), in nanomaggy units (FLUX_W1)
462-473 E12.6 3.63uJy F4.6 [-2704847/5498148] WISE flux in W2
(4.6um), in nanomaggy units (FLUX_W2)
475-487 E13.6 3.63uJy FFg [-92/9471] Predicted g-band flux
within a fiber of diameter 1.5 arcsec
from this object in 1 arcsec Gaussian
seeing, in nanomaggy units
(FIBERFLUX_G)
489-501 E13.6 3.63uJy FFr [-44/12450] Predicted r-band flux
within a fiber of diameter 1.5 arcsec
from this object in 1 arcsec Gaussian
seeing, in nanomaggy units
(FIBERFLUX_R)
503-515 E13.6 3.63uJy FFz [-161/12820] Predicted z-band flux
within a fiber of diameter 1.5 arcsec
from this object in 1 arcsec Gaussian
seeing, in nanomaggy units
(FIBERFLUX_Z)
517-526 F10.6 mas plx [-92.1/161] Reference catalog parallax
(PARALLAX)
528-537 F10.4 s COADD_EXP [0/43506] Summed exposure time for
coadd (COADD_EXPTIME)
539-554 F16.12 deg RAFdeg Mean (over exposures) RA of actual
fiber position (MEANFIBERRA)
556-567 E12.6 arcsec s_RAFdeg [0/106] Standard deviation (over
exposures) of RA of actual fiber
position (STDFIBERRA)
569-584 F16.12 deg DEFdeg Mean (over exposures) DEC of actual
fiber position (MEANFIBERDEC)
586-597 E12.6 arcsec s_DEFdeg [0/110] Standard deviation (over
exposures) of DEC of actual fiber
position (STDFIBERDEC)
599-612 F14.8 d b_MJD Minimum value of the Modified Julian
Date (when the shutter was open for
the first exposure used in the coadded
spectrum) (MIN_MJD)
614-627 F14.8 d B_MJD Maximum value of the Modified Julian
Date (when the shutter was open for
the last exposure used in the coadded
spectrum) (MAX_MJD)
629-642 F14.8 d MJD [59198.1/59744.5] Mean value of the
Modified Julian Date (when the shutter
was open for exposures used in the
coadded spectrum) (MEAN_MJD)
644-655 E12.6 --- TSNR2_ELG ELG template (S/N)^2 summed over B;R;Z
(5)
657-668 E12.6 --- TSNR2_GPBBGHT Template (S/N)^2 for bright targets in
guider pass band (TSNR2_GPBBRIGHT)
670-681 E12.6 --- TSNR2_LYA LYA template (S/N)^2 summed over B;R;Z
(6)
683-694 E12.6 --- TSNR2_BGS BGS template (S/N)^2 summed over B;R;Z
(5)
696-707 E12.6 --- TSNR2_GPBBCK Template (S/N)^2 for backup targets in
guider pass band (TSNR2_GPBBACKUP) (5)
709-720 E12.6 --- TSNR2_QSO QSO template (S/N)^2 summed over B;R;Z
(5)
722-733 E12.6 --- TSNR2_LRG LRG template (S/N)^2 summed over B;R;Z
(5)
735 I1 --- MAIN_PRIM [0/1] Boolean flag (True/False) for
the primary coadded spectrum in Main
survey (MAIN_PRIMARY)
737 I1 --- SV_PRIM [0/1] Boolean flag (True/False) for
the primary coadded spectrum in survey
validation (SV1+2+3) (SV_PRIMARY) (7)
739 I1 --- m_TargetID [1/8] Number of times this TARGETID
appears in this catalog (ZCAT_NSPEC)
741 I1 --- ZCAT_PRIM [0/1] Boolean flag (True/False) for
the primary coadded spectrum in this
zcatalog (ZCAT_PRIMARY)
743-764 A22 --- Name Human readable identifier of a sky
location (DESI Jddd.dddd+dd.dddd; with
truncated decimal RAICRS/DEICRS;
precise to 0.36"). Multiple objects
can map to a single Name if very close
on the sky (DESINAME)
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Note (1): Type as follows:
GALAXY = 21,696,490 occurrences
QSO = 1,862,583 occurrences
STAR = 4,866,890 occurrences
Note (2): See
http://desidatamodel.readthedocs.io/en/latest/bitmasks.html#fiberstatus
Note (3): See http://www.legacysurvey.org/release/
Note (4): Morphological type are described here:
http://www.legacysurvey.org/dr9/catalogs/
#goodness-of-fits-and-morphological-type
Note (5): BGS = Bright Galaxy Survey targets from Hahn+ 2023AJ....165..253H 2023AJ....165..253H
ELG = Emission Line Galaxies from Raichoor+ 2023AJ....165..126R 2023AJ....165..126R
QSO = quasars targets from Chaussidon+ 2023ApJ...944..107C 2023ApJ...944..107C
LRG = Luminous Red Galaxies from Zhou+ 2024ApJ...961..173Z 2024ApJ...961..173Z
GPBBCK = Backup targets; part of the Milky Way Survey; Dey+ 2025 in prep.
Note (6): Here, LYA refers to QSOs which have been spectroscopically confirmed
to be Lyα forest (z>2.1) quasars.
Note (7): Although the primary focus of DR1 is on the new main-survey data,
DR1 also includes all the survey validation (SV) data which were taken
before the start of the main survey:
1. SV1 (Target Selection Validation) tiles were used to verify and
refine the target-selection algorithms for the main survey, and
include dedicated secondary-target tiles which were used for special
programs before we developed the special survey (see Section 2.3.3).
2. SV2 (Operations Development) tiles were used to test survey-like
DESI operations; and
3. SV3 (One Percent Survey) tiles comprised a high-completeness sample
of observations using the final set of DESI target selection algorithms.
--------------------------------------------------------------------------------
History:
From http://data.desi.lbl.gov/public/dr1/spectro/redux/iron/zcatalog/
v1/zall-pix-iron.fits
License:
The Dark Energy Spectroscopic Instrument (DESI) data are licensed
under the Creative Commons Attribution 4.0 International License ("CC
BY 4.0", [Summary](https://creativecommons.org/licenses/by/4.0/),
[Full Legal
Code](https://creativecommons.org/licenses/by/4.0/legalcode)). Users
are free to share, copy, redistribute, adapt, transform and build upon
the DESI data available through this website for any purpose,
including commercially.
(End) F.-X. Pineau, G. Monari & E. Perret [CDS] 23-Jun-2025