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eROSITA All-Sky Survey (First 6 Months) Three-Band (2.3-5.0 keV) Source Catalog

Metadata Updated: August 30, 2025

The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019, with the aim of producing all-sky X-ray source lists and sky maps of an unprecedented depth. The authors present catalogs of both point-like and extended sources using the data acquired in the first six months of survey operations (eRASS1; completed June 2020) over the half sky whose proprietary data rights lie with the German eROSITA Consortium. This catalog contains all X-ray sources detected in the 2.3-5 keV band with detection likelihood > 12. The 5466 sources detected in the less sensitive but harder 2.3-5 keV band is the result of the first true imaging survey of the entire sky above 2 keV. The eRASS1 main catalog, <a href="/W3Browse/erosita/erass1main.html">eRASS1MAIN</a>, contains nearly 930000 entries detected in the most sensitive 0.2-2.3 keV energy range and the sources (only the strongly associated ones) from the main catalog have been linked to eRASS1MAIN in this catalog. The reference paper presents methods to identify and flag potential spurious sources in the catalogs, which were applied for this work, and the authors tested and validated the astrometric accuracy via cross-comparison with other X-ray and multi-wavelength catalogs. The catalogs form part of the first data release (DR1) of the SRG/eROSITA all-sky survey. Beyond the X-ray catalogs, DR1 contains all detected and calibrated event files, source products (light curves and spectra), and all-sky maps. The data files are linked to the table and also accessible from the <a href="/docs/srg/erosita/">HEASARC eROSITA</a> and <a href="https://erosita.mpe.mpg.de/dr1/">eROSITA-DE ERASS1</a> websites. The catalog uses the following designation for indicating the bands for the different measurement: <pre> Band Energy range (keV) 0 0.2 - 5.0 1 0.2 - 0.6 2 0.6 - 2.3 3 2.3 - 5.0 </pre> This database table was ingested by the HEASARC in June 2024 and is based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/682/A34">CDS Catalog J/A+A/682/A34</a> file erass1-h.dat. In some cases, the HEASARC has altered the original field names, as per HEASARC conventions, and provides the original field names in square brackets. This is a service provided by NASA HEASARC .

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.

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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 High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/erass1hard
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 0847b294-66df-4cd4-9b86-b9f47dc92c2a
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/erass1hard.html
Program Code 026:000
Source Datajson Identifier True
Source Hash a310c65674f1634fff7a79b5e3aa8d6db3da2994b7b489c9586b65c0c10b905a
Source Schema Version 1.1

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