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ROSAT data and PROS

There have been major changes throughout the system (PROS release 2.3) to accomodate the Rationalized Data Format (RDF). For ROSAT this has meant a change in the existing data file formats, and also a standardization between US, UK and MPE data-set formats; hence all Rev 2 ROSAT re-processed data will be in a common format, regardless of where it was processed. Information on the new ROSAT RDF data files can be found in help explain_xdata.

Of course, there is still a large quantity of ROSAT data distributed in the US REV0 format. PROS will continue to support input files in either format, but PROS tasks will always write output files in the NEW (RDF compatible) format. The PROS ROSAT FITS readers (rfits2pros, rarc2pros) will do any required conversions automatically. However, any EXISTING PROS QPOE files, must be converted manually by the user, with the task upqpoerdf.

        xr> xdataio
        xd> upqpoerdf *.qp

Existing image files can be updated with the task, upimgrdf.

        xr> xdataio
        xd> upimgrdf *.imh
Several of the header keywords are changed by this process. Also, in the case of the ROSAT/HRI the de-gapped HRI coordiantes (detx, dety) are calculated by applying the gapmap to the raw telemtry coordinates (rawx,rawy). These changes from existing US Rev0 format to RDF format are described in help file_compare.

One of the additional features of the new RDF format for ROSAT data is the inclusion of the `rejected' events. Both PSPC and HRI do spatial and temporal screening of the event-list before analysis by the pipeline SASS processing system. Previously, only the photon-events that passed this standard screening process were available to users. With the RDF format and Rev 2 processing, an additional extension of 'rejected' events is available. Access to these events

Two new tasks, hkfilter and mkhkscr, are provided to allow users to build QPOE filters for non-standard event screening. Descriptions of these tasks and additional information on how to use and manipulate these data are available in help explain_screens.

N.B.: Time and Date ROSAT dates, in the headers, follow the FITS standard or European style, DD/MM/YY (not the American style, MM/DD/YY). The times of events are measured in seconds from the time of launch [21:06:50, day 152, yr 1990 (1 June 1990)].

Time is measured with the spacecraft clock. These times must be converted to UT or barycentered times for precise work. See xtiming.timcor packages for information.



 
next up previous contents
Next: *rfits2pros* - PI Data Up: DATA I/O Previous: *xrfits, mperfits* - FITS
rsdc@cfa.harvard.edu
1998-06-10