XMM-Newton Users' Handbook

5 Proposal Submission and Optimisation

Since AO-3 the proposal submission process for XMM-Newton is divided into two phases:

In response to the call, principal investigators (PIs) will be asked to provide the scientific justification and some major source and observing parameters, like coordinates, observation duration and observing mode of the prime instrument. This will be done using the well known HEASARC developed RPS.

During the second phase of the proposal submission, only successful PIs will be asked to provide the exposure parameters in full detail via the Remote Proposal Submission software (XRPS). After submission each proposal will undergo a technical proposal optimisation (the so called ``proposal enhancement'') by SOC personnel. Note that it is the proposer's responsibility to ensure that the target coordinates (and, if necessary, the satellite position angle) are correct.

The technical optimisation of these proposals will consider the following points:

• EPIC
  1. expected X-ray counts
     Calculating the expected X-ray counts for the specified target for each filter of each EPIC instrument.
  2. expected optical count rate
     Calculating the expected optical counts for each specified target for each filter of each EPIC instrument.
  3. telemetry bandwidth
     Calculating the expected telemetry bandwidth for each exposure.
  4. science parameter
     Calculating for each exposure the:
     • expected pile-up
     • counts per frame

• RGS
  1. expected X-ray count rate
     Calculating the expected X-ray counts for the specified target for each RGS instrument.
  2. telemetry bandwidth
     Calculating the expected telemetry bandwidth for each exposure.
  3. science parameter
     Estimating for each exposure if pile-up may be present from the expected X-ray count rate.

• OM
  1. image mode count rate estimation
     Calculating the counts expected in each imaging mode window of each OM exposure.
  2. fast mode count rate estimation
     Calculating the counts expected in each fast mode window of each exposure.
  3. fast mode time slice estimation
     Calculating the fast mode time slice duration, for each fast mode window, in units of the MIC frame time. The PI originally specifies the time slice duration of each fast mode window in ms.
  4. tracking frame time estimation
     Calculating the OM tracking frame time, for each exposure, in units of the DPU cycle. The exposure duration, originally specified by the PI in seconds, is then calculated as an integer multiple of this tracking frame time.
  5. science windows
     • Calculating the size of the window, in detector pixels, for each science window that is specified by the PI in arc-seconds. If the PI has specified a window in detector pixels then this value is output.
     • Assigning a blue fast mode area (1 or 2) to each fast mode window.
     • Calculating the number of memory windows required to enclose the specified science windows and their details (position and size).
  6. bright object and guide stars
     For each observation indicating:
     • whether the observation is possible with any filter (not just those specified by the PI).
     • for which filters there are potential bright sources in the field of view.
     • the position angle constraints, if any, which would ensure that these bright sources do not appear in the field of view.
     • the potential guide stars for the observation. The right ascension, declination and visible magnitude of up to 32 stars are generated.

PIs will always be informed about the outcome of the evaluation described above. All changes of observation parameters have to be confirmed explicitly by the PIs. This is a pre-condition for an observation to be included in the scheduling system (cf.
http://xmm.esac.esa.int/external/xmm_sched/enhancement.shtml).