XMM-Newton Status Report - February 2003
The work on upgrading the mission operations center (MOC) to SCOS-2000 (as reported before) has started and is running on schedule. Following reduction of the operational temperature of the EPIC-MOS' and RGS' CCDs, in order to ameliorate some of the radiation damage incurred so far, data processing and data shipment had to be stopped for some 6-8 weeks because a new set of calibration files had to be derived. This exercise was successfully completed by mid-January 2003, and data processing and shipment has resumed.
Operations and archiving
The programme completion status is as follows: Guaranteed time: 95.5 %; AO-1 programme: 91.0 %; AO-2 programme: 18.6 %. Completion of all of the above observing programmes is expected by November 2003. The release of the call for observing proposals for AO-3 is planned for March 17, 2003. The results from the proposal review will be available by early July 2003. The OTAC for the AO-3 review has been nominated. Coming AO-3, XMM-Newton will start using a dual stage proposal submission process in order to prevent the problems encountered in the AO-2 proposal submission process.
The status of data processing and data shipment is, following the interruption related to the instrument cooling exercise reported above, once again, nominal. Currently, over 2300 observation sequences have been executed and the data for 2100 of these has been shipped. Version 1.5 of the XMM-Newton Science Archive was successfully released, as planned, for use by the wide astronomical community in mid-November 2002.
The next meeting of the users group will be on 31st March- 1 st April 2003.
The results of an XMM-Newton observation of the X-ray binary EXO 0748-676 were published in Nature on 7 November 2002. The Paper reported the discovery of significant absorption lines in the spectra of 28 bursts of this so-called low-mass X-ray binary. The most significant features were identified with the Fe XXVI and XXV n = 2-3 and O VIII n = 1-2 transitions, all with a redshift of z = 0.35, identical within small uncertainties for the respective transitions. For an astrophysically plausible range of masses (M ~ 1.3-2.0 Solar Mass), this value is completely consistent with models of neutron stars composed of normal nuclear matter, while it excludes some models in which the neutron stars are made of more exotic matter.