XMM-Newton-NEWS  #32,    7-Apr-2003

ESA, XMM-Newton Science Operations Centre at
European Space Astronomy Centre (ESAC)
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XMM-Newton Serendipitous Source Catalogue released

We are pleased to announce the release of the first XMM-Newton Serendipitous Source Catalogue: 1XMM.

1XMM is the first comprehensive catalogue of serendipitous X-ray sources from the European Space Agency's (ESA) XMM-Newton observatory, and has been constructed by the XMM-Newton Survey Science Centre (SSC) on behalf of ESA. Most (> 80%) of the entries have not previously been reported as X-ray sources. This catalogue is expected to become a significant astronomical resource, as it is the largest catalogue of X-ray sources derived from observations with CCD energy resolution over the full 0.2-12 keV energy band.

The catalogue contains source detections drawn from 585 XMM-Newton EPIC observations made between 2000 March 1 and 2002 May 5; all datasets were publicly available by 2003 January 31 but not all public observations are included in this catalogue. Net exposure times in these observations range from < 1000 up to ~100000 seconds. The total area of the catalogue fields is ~90 deg^2, but taking account of the substantial overlaps between observations, the net sky area covered independently is ~50 deg^2. The observations sample, albeit sparsely, most of the sky, with the exception of a 'hole' centred in the Cygnus region caused by spacecraft observing constraints.

The catalogue has been made by reprocessing suitable EPIC data with the most recent software and calibrations available. The processing system used was based on the SSC routine processing pipeline used to produce data products for the observers and the archive, and new versions of the EPIC products (including event lists) are available in association with the catalogue. Considerable effort has been expended to 'calibrate' the catalogue in terms of understanding such issues as errors, biases, sensitivity and sky coverage. Extensive documentation describes the catalogue production, qualities and content.

The catalogue source detection and parametrisation technique is optimised for point-like sources, and has been performed across several photon-energy bands and using data from each of the three EPIC cameras - PN, MOS1, MOS2.

The catalogue content includes the source-detection parameters (likelihood, position coordinates, counts, count rate, flux, hardness ratio, background estimates, errors ...); the results of cross-correlation with a large number of archival catalogues (SIMBAD, NED, USNO, GSC, APM, ROSAT ...); quality 'flags' resulting from visual screening, and 'metadata' relating to the observation.

The catalogue contains 33026 X-ray source detections with likelihood values >8 and summary quality flag >0, together with a further 23685 detections with lower likelihood values and/or summary quality flag=0. These latter sources have lower reliability, since those with quality flag=0 are deemed to be false detections due to processing deficiencies, whilst at likelihoods below 8 the fraction of spurious sources expected on a statistical basis increases rapidly.

The median flux (in the total photon energy band 0.2-12 keV) of the catalogue sources is ~3e-14 erg cm^-2 s^-1; ~12% have fluxes below 1e-14 erg cm^-2 s^-1.

The positional accuracy of the catalogue sources is generally ~0.5-2 arcsec (68% confidence radius) for detections with likelihood >8. The flux estimates from the three EPIC cameras are overall in agreement to ~2% for on-axis sources, and ~6% off-axis.

In association with the catalogue itself, various data products are also available (images, exposure maps, sensitivity maps, extracts from archival catalogues and databases ...).

The catalogue is available in several forms and from several servers:

XSA, XCAT-DB and LEDAS provide a Web-based user interface allowing filtering and searching of the catalogue, and links to associated data products. The SSC Home Page, XSA and Vizier allow download of the catalogue file in (binary) FITS. The SSC Home Page also provides a plain ASCII-text version.

Access to the catalogue will also very soon be provided by Vizier;http://vizier.u-strasbg.fr/

XSA Version 2.0

Version 2.0 of the XMM-Newton Science Archive (XSA) is now available. You may access the user interface at the URL:

Potential XSA users may refer to the following URL for a brief introduction to the XSA usage and functionalities:

The main improvements in this version can be summarized as follows:
  1. access to the XMM-Newton source catalogue. This implies an extensive querying facility on a wide range of observation- and source related parameters, together with source catalogue parameter display, visualization of finding charts and source images, and retrieval of the corresponding XMM-Newton datasets (ODFs and/or PPS products)
  2. first public version of the Archive InterOperability system (AIO). This system allows XMM-Newton users to have direct access to the content of the XSA database without invoking the XSA user interface applet: ODF and/or PPS files for a given observation as well as individual PPS products or customized sets of individual PPS products can be retrieved either via a server socket (run either through a user defined client or an XML file), or through a URL address. Users interested in using this system are encouraged to contact the XMM-Newton HelpDesk.
  3. sorting of the query results according to: distance to the nominal pointing, observation start time, observation ID, proprietary right expire date, or total source counts
  4. direct access to a wide range of XMM-Newton related documents from the user interface applet
  5. possibility of combining exposure constraints according to AND or OR logic
  6. new Frequently Asked Question page, containing practical recipes on how to accomplish specific search and data retrieval tasks. It is available at the URL: http://xmm.esac.esa.int/xsa/docs/xsa_faq_usage.shtml
  7. access to proposal abstracts from the XSA user interface, under the menu "Details" of each observation catalogue record.

Scientific justification of AO-3 proposals

The requirements of the scientific justification of AO-3 proposals are described in the "Policies and Procedures for the XMM-Newton AO-3", page 15, see URL: http://xmm.esac.esa.int/external/xmm_science/AO3/ao3_policy_proc/node22.shtml

In summary they are:
format; postscript
size limit; 10 MByte
page limit; 4 pages
font size; greater/equal 10 pt

It is allowed to submit scientific justifications in colour postscript. The proposals gets shipped to the review panels on CD's. Consequently, individual panel members may print these in b/w only.

A LaTex template to write the scientific justification is provided at:

Calibration Status documents updated

The XMM-Newton calibration scientists and instrument teams have updated the documents describing the current status of the EPIC, RGS and OM calibration. These are available again from the XMM-Newton Calibration Portal under the heading 'What is the current status of the calibration?', see

Analysing post cooling data

The cooling of RGS2 was the first step of the RGS and EPIC MOS cooling campaign. It took place in the night November 3-4 2002 during XMM-Newton revolution 532. The two EPIC MOS instruments were cooled in the night of November 6-7 2002 and finally the RGS1 CCD bench was cooled in the night November 13-14 2002 during revolution 538 (see XMM-NEWTON NEWS#27).

As the cooling resulted in major reductions in hot pixels and hot columns, and reduction by some factors in charge-transfer inefficiency (CTI), the user analysing post cooling data must make use of the XMM-Newton Science Analysis System (SAS) version 5.4 onwards. Only this SAS version takes into account the changed calibration of RGS and MOS post cooling data.

XMM-Newton ToO observation of XTE J1807-294

Information on the XMM-Newton target of opportunity (ToO) observation of the millisecond X-rays pulsar XTE J1807-294 discovered by XTE on February 21, 2003 are available at the following URL:

On this page you find preliminary data processing results like images and spectra together with info on the availability of related data sets (ODF and PPS products).

Yours sincerely,
XMM-Newton SOC