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4XMM-DR11

The 4XMM-DR11 catalogue contains source detections drawn from 12210 XMM-Newton EPIC observations, covering an energy interval from 0.2 keV to 12 keV. These observations were made between 2000 February 3 and 2020 December 17 and all datasets were publicly available by 2020 December 17, but not all public observations are included in this catalogue (see below for more information).

Should you use the catalogue for your research and publish the results, please use the acknowledgement below and cite the paper describing 4XMM (Webb et al., 2020).

This research has made use of data obtained from the 4XMM XMM-Newton serendipitous source catalogue compiled by the 10 institutes of the XMM-Newton Survey Science Centre selected by ESA.

As well as the fits and csv formats of the catalogue distributed below, the following Web-based user interfaces will allow filtering and searching of the catalogue (and give access to all or selected associated data products):

The SSC Catalogue Home Page (this page), XSA, and HEASARC allow download of the catalogue file in (binary) FITS. Summary pages and products are already available in the IRAP catalogue server.

The cross-correlation products of potential counterparts at other wavelengths for 4XMM-DR11 are provided through the XCAT-DB and the IRAP catalogue server.

We also provide Multi-Order-Coverage maps (MOCs) for 4XMM-DR11. MOCs for individual observations in fits format can be downloaded via the catalogue server (identified through their OBSIDs). The MOC covering the whole of 4XMM-DR11 field is available here. Amongst other ways to use the MOCs, we recommend the python tool MOCpy. We also provide EPIC flux maps for each observation, where each point on the map provides the limiting flux for a source detected at 3 sigma in the 0.2-12.0 keV band (assuming a power law spectrum with a photon index of 1.42 and an nH of 1.7x1020 cm-2) here and rate maps here. Alternatively, they can be accessed through the IRAP catalogue server, provided at the top of the page for each individual detection of the sources in the field of view.
The following table gives an overview of the statistics of the catalogue in comparison with the 4XMM-DR10 catalogue.

  4XMM-DR11 4XMM-DR10 Increment
Number of observations 12210 11647 563
Number of 'clean' observations (i.e., observation class < 3) 10247 9784 463
Observing interval 03-Feb-00 -- 17-Dec-20 03-Feb-00 -- 14-Dec-19 1 yr
Sky coverage, taking overlaps into account ( ≥  1ksec exposure) 1239 sq.deg 1192 sq.deg 47 sq.deg
Number of detections 895415 849991 45424
Number of 'clean' detections (i.e., summary flag < 3) 787963 748670 39293
Number of unique sources 602543 575158 27385
Number of 'cleanest' (summary flag = 0, not in high-background fields) extended detections 19077 18093 984
Number of detections with spectra 319565 303023 16542
Number of detections with timeseries 319292 302773 16519
Number of detections where probability of timeseries being constant is  <  1  × 10-5 7283 6972 311

The median flux in the total photon energy band (0.2 - 12 keV) of the catalogue detections is ~ 2.3 × 10-14 erg cm-2 s-1; in the soft energy band (0.2 - 2 keV) the median flux is ~ 5.2 × 10-15, and in the hard band (2 - 12 keV) it is ~ 1.2 × 10-14. About 23% of the sources have total fluxes below 1 × 10-14 erg cm-2 s-1.

About a tenth of the observations have features that may cause spurious detections (mainly the wings of bright sources and large extended emission), and it is strongly recommended to use a filter (both per source, based on the summary flag column, and per observation, based on the observation class column).


Access

The 4XMM-DR11 catalogue, released on 2021 August 18th, is available in several formats:

Please read the Watchouts section before using the catalogues.

4XMM_DR11cat_v1.0.fits.gz FITS binary 834 MB MD5: a286efef7629dc144be6acfe35a1e24a full binary catalogue; recommended for more in-depth studies (includes information of all detections)
4XMM_DR11cat_v1.0.csv.gz CSV 1021 MB MD5: c179f42664383ed442e6aaa092e459c7 full ascii catalogue
4XMM_DR11cat_slim_v1.0.fits.gz FITS binary 81 MB MD5: 6601344846c006e9dee1aabcc5dd1541 reduced binary catalogue, suited for studies of unique sources (individual detection information is not included)
4XMM_DR11cat_slim_v1.0.csv.gz CSV 104 MB MD5: 46bd98fd0829dcc28340e07a20268ea6 reduced ascii catalogue

For convenience, there are suitable SQL CREATE statements available for use with a relational DBMS in order to load the data in CSV format:

The CSV file has nulls represented by two successive commas, compatible with Postgres and (probably) other DBMS.

The slimline version of the catalogue contains one row per unique source (while the the main catalogue has one row per detection) and thus has 602543 rows. There are 45 columns, essentially those containing information about the unique sources. The catalogue also contains a column with links to the IRAP catalogue server summary pages. In the case of sources with multiple detections, the summary page of the best detection is selected (i.e., the detection with the largest exposure time, summed over all cameras), and the summary page gives cross-links to the other detections.

A separate file is also provided (table below) which contains key details about the observations used in the construction of the 4XMM-DR9 catalogue. See the list of observations for a description of the columns in the file.

4xmmdr11_obslist.fits FITS binary 1.4 MB MD5: ef6ca63ebf94862b30ca4f168738d9d1 Summary table of observations used in the catalogue

Documentation

The User Guide for the 4XMM-DR11 catalogue contains details of the catalogue production process and content. Here are quick links to


Watchouts for 4XMM

1) In the 4XMM-DR9 version, the systematic error used was a factor √(2) too small. This has been corrected in 4XMM-DR10 and it has been revised for the 4XMM-DR10 version (see Webb et al. 2020 for more details) to 1.9''. The same value is still valid for 4XMM-DR11.

2) As in 4XMM-DR9, we now use the flag 12 to indicate if the detection lies on/close to a warm pixel. Note, this is not propagated into the SUM_FLAG value.

3) As in 4XMM-DR9, the catalogue includes values for the pileup for both point-like and extended sources. Some pileup values for extended sources were deemed to be erroneous and therefore all pileup values for extended sources are NULL in the 4XMM-DR10 and 4XMM-DR11 versions.


Nomenclature and Citation

With the 4XMM catalogue, IAU name nomenclature includes the designator, 4XMM. The IAU name is provided in the catalogue. The correct, full nomenclature for a specific detection from the catalogues is the IAU name, followed by a colon and the detection identification number, that is:"4XMM Jhhmmss.sSddmmss:detid". For the stacked catalogue it is:"4XMMs Jhhmmss.sSddmmss:detid"

Credits

The production of the 4XMM-DR11 catalogue is a collaborative project involving the whole XMM-Newton SSC Consortium:

The SSC team are grateful to the XMM-Newton SOC for their support in the catalogue production activities.

The SSC acknowledges the use of the TOPCAT and STILTS software packages (written by Mark Taylor, University of Bristol) in the production and testing of the 4XMM-DR10 catalogue.