Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Skip to content

XMM-Newton Wide Angle Survey

Metadata Updated: September 19, 2025

This table contains results from the XMM-Newton Wide Angle Survey (XWAS), viz., a new catalog of almost a thousand X-ray sources that have been spectroscopically identified through optical observations. The sources lie in high-galactic latitude (|b| > 20 degrees) XMM-Newton fields mainly in the southern hemisphere. A sample of X-ray sources detected in 68 XMM-Newton pointed observations was selected for optical multi-fiber spectroscopy. Optical counterparts and corresponding photometry of the X-ray sources were obtained from the SuperCOSMOS Sky Survey. Candidates for spectroscopy were initially selected with magnitudes down to R ~ 21, with preference for X-ray sources having a flux F<sub>0.5-4.5keV</sub> >= 10<sup>-14</sup> erg/s/cm<sup>2</sup>. Optical spectroscopic observations were made using the Two Degree Field of the Anglo-Australian Telescope, and the resulting spectra were classified based on optical emission lines. The authors have identified through optical spectroscopy 940 X-ray sources over a solid angle Omega ~ 11.8 deg<sup>2</sup> of the sky. Source populations in their sample can be summarized as 65% broad-line active galactic nuclei (BLAGN), 16% narrow emission-line galaxies (NELGs), 6% absorption-line galaxies (ALGs) and 13% stars. An active nucleus is also likely to be present in the large majority of the X-ray sources spectroscopically classified as NELGs or ALGs. Optical images are available for all of the XWAS fields in the SuperCOSMOS Sky Survey (Hambly et al., 2001, MNRAS, 326, 1279). This table was created by the HEASARC in May 2017 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/557/A123">CDS Catalog J/A+A/557/A123</a> file xwas_cat.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

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/xwas
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 0ec0c720-db62-4b23-8991-ca533872f07b
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/xwas.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 2c78f6189c2d344e1a44c785c71cbe6f9b1554056813af11bd42173d6f64954e
Source Schema Version 1.1

Didn't find what you're looking for? Suggest a dataset here.