XMM-Newton Source Designations

Naming conventions for XMM-Newton sources found by individual researchers

The XMM-Newton Observatory produces serendipitous catalogues of typically 10's of X-ray sources and additional Optical/UV targets for each and every observation.

While the eventual comprehensive catalogues will be produced by pipeline processing of data by the XMM-Newton Survey Science Centre the following interim designation for identification in individual fields is recommended (and approved by the IAU "Clearing House" of Commission 5 Working Group on Designations);

If referring to detected sources in XMM-Newton fields one should follow the naming convention XMMU JHHMMSS.s+/-DDMMSS.

Here are a couple of examples;

Source Position Recommended Acronym
RA 03 10 15.1, Dec -76 51 31.2 (J2000) XMMU J031015.1-765131
RA 17 23 48.7, Dec +82 17 33.8 (J2000) XMMU J172348.7+821733

The coordinates for the designation are "truncated" and not "rounded". XMMU is intended to be used for those serendipitous sources which need to be referenced in a paper (see also http://vizier.u-strasbg.fr/cgi-bin/Dic?XMMU).

Where the full set of detected sources in one or multiple XMM-Newton fields is to be specified or discussed the recommendation is to designate the set XMMAA, XMM AAAA, etc. Where AA or AAA represent the authors' initials, and should be used for surveys provided that the authors have submitted their acronym to the Acronym Registry (for further details see the IAU Specifications for Nomenclature web page at http://cdsweb.u-strasbg.fr/iau-spec.html).

The discussion on how to name OM detected sources is still ongoing with the "Clearing House" members. For the time being the proposal is to name them XAU JHHMMSS.s+/-DDMMSS to distinguish them from XMM-Newton sources detected in X-rays (see also http://vizier.u-strasbg.fr/cgi-bin/Dic?XAU).