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    • XMM-Newton Large-Scale Structure X-Ray Source Catalog

    Metadata Updated: March 13, 2026

    The XMM-Newton Large-Scale Structure (XMM-LSS) X-Ray Source Catalog contains the source list for the first 5.5 surveyed square degrees of the XMM-LSS, with a total of 3385 point-like or extended sources above a detection likelihood of 15 in either 0.5 - 2 keV or 2 - 10 keV bands. The agreement with deep log N- log S is excellent. The main parameters considered are position, count rate, source extent with associated likelihood values. A set of additional quantities such as astrometric corrections and fluxes are further calculated while errors on the position and count rate are deduced from simulations. This table contains the main parameters, while further parameters and data products (X-ray images and optical thumbnails) are available at the Milan XMM-LSS database site: <a href="http://cosmos.iasf-milano.inaf.it/~lssadmin/Website/LSS/Query">http://cosmos.iasf-milano.inaf.it/~lssadmin/Website/LSS/Query</a>; This table was created by the HEASARC in February 2008 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/382/279">CDS Catalog J/MNRAS/382/279</a> file xlss.dat. This is a service provided by NASA HEASARC .

    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 March 13, 2026

    Metadata Source

    Harvested from NASA Data.json

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date April 11, 2025
    Metadata Updated Date March 13, 2026
    Publisher High Energy Astrophysics Science Archive Research Center
    Maintainer
    Identifier ivo://nasa.heasarc/xmmlss
    Data Last Modified 2026-03-09
    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 38deaf18-9e14-4dee-b7cc-0edbcfe3d91f
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    Homepage URL ivo://nasa.heasarc/xmmlss
    License https://www.usa.gov/government-works
    Program Code 026:000
    Source Datajson Identifier True
    Source Hash 2421c6c1175c9e963db9336a0f6269a1c045bd2b9f5945a23b4a4a5af6210006
    Source Schema Version 1.1

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