ASTRA-DESI DR1 Release v0.12

2025/03/18 by DESI Collaboration, Karim, M. Abdul, M. Abdul Karim +600 · 2 voices · 45 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Dark Matter and Cosmic Phenomena #Galaxies: Formation, Evolution, Phenomena #astro-ph.CO

paper · pdf · doi:10.48550/arxiv.2503.14745

openalex publication_date 2025/03/18 · openalex created_date 2025/10/07 · openalex updated_date 2026/07/28

Abstract

ASTRA-DESI Data Release 1 (DR1) This record bundles the ASTRA-DESI DR1 products for the two DESI survey regions (NGC and SGC). Every catalogue is delivered as a compressed FITS binary table (.fits.gz) whose first extension (HDU 1) contains the data. File headers store the keywords RELEASE=DR1 and the corresponding ZONE label for quick checks. The sky partition used in this release is mask-based rather than box-based. The survey footprint is defined as a HEALPix mask combining DESI tile coverage and LSS object coverage, requiring a minimum completeness threshold of ≥4 tiles per pixel. The resulting mask is then split into NGC and SGC according to the right ascension of the HEALPix pixel centers. Tracer Number of objects BGS BRIGHT 305,900 LRG 78,668 ELG 119,015 QSO 100,331 Directory layout The archive preserves the NERSC production tree. Top-level folders contain: raw/ – merged real and random catalogues per region. classification/ – neighbour count summaries per tracer and random iteration. probabilities/ – web-type membership probabilities derived from the classification counts. groups/ – watershed groups for a given tracer and region (NGC or SGC). Naming conventions raw/zone_REGION.fits.gz – Region NGC or SGC. classification/zone_REGION_classified.fits.gz – combined tracer summary for the region. probabilities/zone_REGION_probability.fits.gz – per-object web-type probabilities. groups/TYPE_TRACER_REGION.fits.gz – per-object web-type groups. Column reference Raw catalogues (raw/*.fits.gz) Column Type Description TARGETID int64 DESI target identifier. RA float64 Right ascension in degrees. DEC float64 Declination in degrees. Z float64 Spectroscopic redshift. XCART, YCART, ZCART float64 Comoving Cartesian coordinates (Mpc) computed with the Planck18 cosmology. TRACERTYPE string Tracer label with suffix _DATA or _RAND (BGS_BRIGHT, ELG, LRG, QSO). RANDITER int32 -1 for real objects, otherwise the random iteration index (0–99). SED_SFR float64 Star formation rate derived from SED fitting. SED_MASS float64 Stellar mass derived from SED fitting. FLUX_G float64 Observed flux in the g photometric band. FLUX_R float64 Observed flux in the r photometric band. Each raw file merges all tracers for its zone. Random catalogues mirror the data counts for every tracer and random iteration. Additional columns SED_SFR, SED_MASS, FLUX_G, and FLUX_R were incorporated from the DESI DR1 value-added catalogues associated with the emission-line sample: https://data.desi.lbl.gov/doc/releases/dr1/vac/stellar-mass-emline/. These quantities are derived via SED fitting using CIGALE (Zou et al. 2024). Classification catalogues (classification/*.fits.gz) Column Type Description TARGETID int64 Identifier of the central object. RANDITER int32 -1 for data rows, otherwise the random catalogue index. ISDATA bool True for data rows; False for random iterations. NDATA int32 Number of neighbour pairs built from data tracers for this target. NRAND int32 Number of neighbour pairs contributed by random tracers. TRACERTYPE string Tracer family (BGS_BRIGHT, ELG, LRG, QSO). Probability catalogues (probabilities/*.fits.gz) Column Type Description TARGETID int64 Identifier of the object. TRACERTYPE string Tracer family. PVOID float32 Probability of the object being a void class. PSHEET float32 Probability of the sheet class. PFILAMENT float32 Probability of the filament class. PKNOT float32 Probability of the knot class. Watershed group catalogues Each file contains a primary header plus two binary-table extensions: HDU 1: VOIDS (one row per retained group). HDU 2: POINT_MEMBERSHIP (one row per data/random point). Primary-header keywords include TRACER, CAP, NVOIDS, H, OMEGA_M, RTHRESH, and WMODE. - Group catalogues (VOIDS, HDU 1) Column Type Description VOID_ID int32 Group identifier. N_DATA_IN_GROUP int32 Number of data members in the group. N_RAND_IN_GROUP int32 Number of random members in the group. RA float64 Group center right ascension (deg). DEC float64 Group center declination (deg). REDSHIFT float64 Redshift of the group center from comoving-distance inversion. X, Y, Z float64 Group center Cartesian coordinates (Mpc/h). R_EFF float64 Effective RMS radius of members around the group center (Mpc/h). SEMI_AXIS_A, SEMI_AXIS_B, SEMI_AXIS_C float64 Principal semi-axes from the inertia tensor (Mpc/h). ELLIP float32 Ellipticity, defined as 1 - C/A. - Point membership (POINT_MEMBERSHIP, HDU 2) Column Type Description NODE_INDEX int32 Internal index in the combined data+random graph. TARGETID int64 DESI target identifier. IS_DATA int8 1 for data rows, 0 for random rows. GROUPID int32 Assigned watershed group ID; -1 means unassigned. VOID_CLASS_ID int8 Reserved class field (default -1). VOID_CLASS string Reserved class label (default unknown). R float32 Local contrast statistic. N_DATA int32 Number of data neighbours. N_RAND int32 Number of random neighbours. RA, DEC, Z float64 Sky coordinates and redshift of each point. X_CART, Y_CART, Z_CART float64 Cartesian coordinates (Mpc/h). Using the catalogues All FITS tables are compressed with gzip. Random catalogues use RANDITER values 0–99; filtering on RANDITER >= 0 isolates the random iterations. The Cartesian coordinates assume the Planck18 cosmology provided by astropy.cosmology.Planck18. The masks are distributed as a compressed archive (masks.tar.gz) containing FITS maps with the following naming convention: dr1_mask_programnsidenside_final.fits – binary mask defining the valid survey footprint for each program (bright or dark). Pixels with value 1 belong to the footprint, while 0 indicates excluded regions. dr1_mask_programnsidenside_ngc.fits – mask restricted to the North Galactic Cap (NGC). dr1_mask_programnsidenside_sgc.fits – mask restricted to the South Galactic Cap (SGC). Here, program corresponds to the DESI observing program (bright for BGS tracers and dark for LRG, ELG, and QSO), and nside indicates the HEALPix resolution parameter. For reproducibility, additional files are provided: dr1_mask_programnsidenside_maps.npz – compressed NumPy archive containing intermediate maps used in the mask construction, including tile coverage, LSS object counts, and smoothed mask representations.

Cited by

• Observational Evidence for Anisotropic Metal Excess around Galaxies
• Constraining primordial non-Gaussianity from DESI DR1 quasars and Planck PR4 CMB Lensing
• Measurements of quasar proximity zones with the Lyman-α forest of DESI Y1 quasars
• An effective \boldsymbolΛ-Szekeres modelling of the local Universe with Cosmicflows-4
• Varying core-envelope coupling efficiency identified from stellar rotation--activity relation
• The DESI DR1 Peculiar Velocity Survey: global zero-point and H₀ constraints
• The DESI DR1 Peculiar Velocity Survey: growth rate measurements from the maximum likelihood fields method
• Discovery of two little red dots transitioning into quasars
• A measurement of H₀ from DESI DR1 using energy densities
• The miniJPAS and J-NEP surveys: Machine learning for star-galaxy separation
• Lost and Found - A gallery of overlooked optical nuclear transients from the ZTF archive
• Cosmic Shear constraints from HSC Year 3 with clustering calibration of the tomographic redshift distributions from DESI
• Full calibration of the tomographic redshift distribution from the HSC PDR3 Shape Catalog with DESI
• Dark winds on the horizon: Prospects for detecting neutrino and hot dark matter wakes in large-scale structure
• Quasars acting as Strong Lenses Found in DESI DR1
• DESI DR2 Galaxy Luminosity Functions
• Cosmological constraints from the DESI DR1 Bispectrum Full-Shape and DR2 BAO
• Primordial power spectrum reconstructions from BOSS + eBOSS
• AT2025ulz and S250818k: Leveraging DESI spectroscopy in the hunt for a kilonova associated with a sub-solar mass gravitational wave candidate
• QUEST (Quasar Unsupervised Encoder and Synthesis Tool): A machine learning framework to generate quasar spectra
• Multi-Modal Masked Autoencoders for Learning Image-Spectrum Associations for Galaxy Evolution and Cosmology
• H₀ Without the Sound Horizon (or Supernovae): A 2% Measurement in DESI DR1
• Discovery of Repeating Transitions in 25 Changing-look Active Galactic Nuclei
• The anisotropic expansion rate of the local Universe and its covariant cosmographic interpretation
• 4MOST Cosmology Redshift Survey (CRS): Clustering properties of CRS BG and LRG target catalogues
• Cross-correlation of Luminous Red Galaxies with ML-selected AGN in HSC-SSP III: HOD Parameters for Type I and Type II Quasars
• Angular BAO Measurements with the DESI DR1 BGS Sample
• Feeding frenzy in the mighty black holes: what we could learn from them?
• Clustering analysis of medium-band selected high-redshift galaxies
• Impact of Cosmic Filaments on Galaxy Morphological Evolution and Predictions of Early Cosmic Web Structure for Roman
• Inflation, Open Universes, and Dark Energy
• CURLING -- III. Identifying Candidates of Wide-separation Gravitationally Lensed Quasars from the CatNorth Catalogue
• Probing the limits of cosmological information from the Lyman-α forest 2-point correlation functions
• DESI DR1 Lyα 1D power spectrum: Validation of estimators
• Origin of the double-peaked narrow emission-lines in the optical spectra of X-shaped Radio Galaxies
• Exploring Coupled Quintessence in light of CMB and DESI DR2 measurements
• Are arXiv submissions on Wednesday better cited? Introducing Big Data methods in undergraduate courses on scientific computing
• Fiducial-Cosmology-dependent systematics for the DESI 2024 Full-Shape Analysis
• Why Cosmic Voids Matter: Pristine Evolution
• The Impact of Spectroscopic Redshift Errors on Cosmological Measurements
• Early results in the search for extreme coronal line emitters with the Dark Energy Spectroscopic Instrument
• Frequentist Cosmological Constraints from Full-Shape Clustering Measurements in DESI DR1
• A New Paradigm for Testing Gravity: Theory-Independent Constraints Using Data From All Astrophysical and Cosmological Scales
• Measurement of Parity-Violating Modes of the Dark Energy Spectroscopic Instrument (DESI) Year 1 Luminous Red Galaxies' 4-Point Correlation Function
• AllBRICQS: The Discovery of Luminous Quasars in the Northern Hemisphere
• Combined tracer analysis for DESI 2024 BAO

Discussions

• There was also a quick summary of what DESI has on offer for Milky Way enthusiasts. Check out arxiv.org/abs/2503.14745. [bsky, 6 points, 0 comments]
• Currently exploring the DESI data. It is fascinating. Kudos to whoever is responsible for the S in DESI. arxiv.org/pdf/2503.14745 [bsky, 0 points, 1 comments]

Related

• Unraveling the Universe with DESI
• The DESI Experiment, a whitepaper for Snowmass 2013
• The Spectroscopic Data Processing Pipeline for the Dark Energy Spectroscopic Instrument
• The DESI Experiment Part I: Science,Targeting, and Survey Design
• The DESI Experiment Part II: Instrument Design