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SAGE IRAC Epoch 1 and Epoch 2 Catalog

Metadata Updated: August 30, 2025

The Spitzer Space Telescope Survey of the Large Magellanic Cloud Legacy Project Surveying the Agents of a Galaxy's Evolution (SAGE) traces the life cycle of observable matter that drives the evolution of a galaxy's appearance. SAGE has revealed over 6 million sources including ~150,000 evolved stars, ~50,000 young stellar objects and the diffuse interstellar medium with column densities > 1.2×1021 cm -2. The data will provide fundamental insights into the physical processes of the interstellar medium, the formation of new stars and the injection of mass by evolved stars and their relationships on the galaxy-wide scale of the Large Magellanic Cloud.In comparison to the catalog, the archive has more source fluxes (fewer nulled wavelengths) and some more sources but these additions have more uncertainty associated with them. For the catalog, the S/N must be greater than [6, 6, 6, 10] for IRAC bands [3.6um], [4.5um], [5.8um] and [8.0um] for the flux to appear in the corresponding wavelength column. Whereas for the archive, the S/N must be greater than [5, 5, 5, 5] for IRAC bands [3.6um], [4.5um], [5.8um] and [8.0um]. For the catalog, sources with neighbors within a 2" radius are excluded (culled). For the archive, sources within a 0.5" radius are excluded. The difference in criteria for the catalog and archive creation is more complex and described in Section 5.2 of the SAGE Data Delivery Document.This catalog contains Epoch 1 only and Epoch 2 only sources.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date August 30, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date August 30, 2025
Publisher NASA/IPAC Infrared Science Archive
Maintainer
Identifier ivo://irsa.ipac/spitzer/catalog/sage/sagei-ep1ep2cat
Data Last Modified 2025-08-27
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 efe186eb-8861-4074-89d0-d4a5e37023cd
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://irsa.ipac.caltech.edu/data/SPITZER/SAGE/doc/SAGEIRACv3_descriptions.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 039e42d83b9dde60e96c2e79cf72565a40b771fde2a5678799734c35399c9991
Source Schema Version 1.1

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