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Spitzer Deep Wide-Field Survey 8 micron Epoch 4 Catalog

Metadata Updated: April 10, 2026

The Spitzer Deep, Wide-Field Survey (SDWFS) is a four-epoch infrared survey of 10 square degrees in the Boötes field of the NOAO Deep Wide-Field Survey using the IRAC instrument on the Spitzer Space Telescope. SDWFS, a Spitzer Cycle 4 Legacy project, occupies a unique position in the area-depth survey space defined by other Spitzer surveys. The four epochs that make up SDWFS permit - for the first time - the selection of infrared-variable and high proper motion objects over a wide field on timescales of years. Because of its large survey volume, SDWFS is sensitive to galaxies out to z ~ 3 with relatively little impact from cosmic variance for all but the richest systems. The SDWFS data sets will thus be especially useful for characterizing galaxy evolution beyond z ~ 1.5.\n\nThe delivery consists of four band-matched catalogs for each of the four epochs and for the total SDWFS coadd data, a total of 20 catalogs. Vega magnitudes are reported for each IRAC band: 3.6, 4.5, 5.8, and 8 microns. Each source was measured three ways: 4 arcsec diameter aperture, 6 arcsec diameter aperture, and Kron radius aperture (MAG_AUTO in SExtractor). Source coordinates correspond to 2MASS catalog positions to within 0.2 arcsec. The tabulated uncertainties are twice the SExtractor (statistical only) uncertainties as an attempt to account for systematic uncertainties.

Access & Use Information

Public: This dataset is intended for public access and use. License: See this page for license information.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date April 10, 2026

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date April 10, 2026
Publisher NASA/IPAC Infrared Science Archive
Maintainer
Identifier ivo://irsa.ipac/spitzer/catalog/sdwfs/sdwfsi4ep4
Data Last Modified 2026-04-06
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id a610a1e0-fdee-4ab5-b932-df8bb752cd47
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL ivo://irsa.ipac/spitzer/catalog/sdwfs/sdwfsi4ep4
License https://www.usa.gov/government-works
Program Code 026:000
Source Datajson Identifier True
Source Hash 1e8c62ceb87b66f357a0a98aea41e769c9d60cf8934d5b19e128c2e217c8905a
Source Schema Version 1.1

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