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

    Metadata Updated: September 19, 2025

    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: 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 September 19, 2025

    Metadata Source

    Harvested from NASA Data.json

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date April 11, 2025
    Metadata Updated Date September 19, 2025
    Publisher High Energy Astrophysics Science Archive Research Center
    Maintainer
    Identifier ivo://nasa.heasarc/xmmlss
    Data Last Modified 2025-09-10
    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 066c68cf-58f3-4dd3-b45b-90ad0df9e506
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/xmmlss.html
    Program Code 026:000
    Source Datajson Identifier True
    Source Hash d38339714ede7b4ec47d84b483c66f98da5383b815aea32b48f79a49d0185ab5
    Source Schema Version 1.1

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