XMM Users' Handbook

   
Technical proposal optimisation

Upon successful receipt of a proposal by the SOC, the PI will receive an acknowledgement that it has been entered into the system. In the process of proposal preparation for OTAC review, potential conflicts will be identified. Then the proposal will undergo review by the OTAC. Parallel to OTAC review, proposals will be subjected to a technical review 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. After OTAC acceptance, successful proposals will be technically optimised for implementation in the XMM observing program. Technical optimisation of proposals will be performed with the following suite of XMM Proposal Handling Subsystem (PHS) tools:

• EPIC

  1.

  EPIC expected X-ray count rate tool
  This tool calculates the expected X-ray counts for the specified target for each filter of each EPIC instrument.

  2.

  EPIC expected optical count rate tool
  This tool calculates the expected optical counts for each specified target for each filter of each EPIC instrument.

  3.

  EPIC telemetry bandwidth calculation tool
  This tool calculates the expected telemetry bandwidth for each EPIC exposure.

  4.

  EPIC signal to noise ratio tool
  This tool calculates the expected signal to noise ratio for each EPIC exposure.

  5.

  EPIC science parameter calculator tool
  This tool calculates for each EPIC exposure the:

  • expected pile-up
  • fraction of smeared photons
  • duty cycle
  • total number of counts
  • total area of the chosen field of view
  • counts per frame

• RGS

  1.

  RGS expected X-ray count rate tool
  This tool calculates the expected X-ray counts for the specified target for each RGS instrument.

  2.

  RGS expected optical count rate tool
  This tool calculates the expected optical counts for the specified target for each RGS instrument.

  3.

  RGS telemetry bandwidth calculation tool
  This tool calculates the expected telemetry bandwidth for each RGS exposure.

  4.

  RGS diagnostic downlink time estimation tool
  This tool calculates the downlink time associated with the diagnostic data when the RGS instrument is operating in spectroscopy mode.

• OM

  1.

  OM image mode count rate estimation tool
  This tool calculates the counts expected in each imaging mode window of each OM exposure.

  2.

  OM fast mode count rate estimation tool
  This tool calculates the counts expected in each fast mode window of each OM exposure.

  3.

  OM fast mode time slice estimation tool
  This tool calculates the fast mode time slice duration, for each fast mode window, in units of the MIC frame time. GOs originally specify the time slice duration of each fast mode window in ms.

  4.

  OM tracking frame time estimation tool
  This tool calculates the OM tracking frame time, for each exposure, in units of the DPU cycle. The exposure duration, originally specified by GOs in seconds, is then calculated as an integer multiple of this tracking frame time.

  5.

  OM science windows tool
  This tool:

  • calculates the size of the window, in detector pixels, for each science window that is specified by the GO in arc-seconds. If the GO has specified a window in detector pixels then this value is output.
  • assigns a blue fast mode area (1 or 2) to each fast mode window.
  • calculates the number of memory windows required to enclose the specified science windows and their details (position and size).

  6.

  OM telemetry bandwidth calculation tool
  This tool calculates whether the data generated during an exposure can be downlinked during the next exposure using the telemetry bandwidths available to the OM instrument. The tool also indicates the actual bandwidth which can be used and the time taken to downlink the data with this bandwidth.

  7.

  OM bright object and guide star tool
  For each observation this tool will indicate:

  • whether the observation is possible with any filter (not just those specified by the GO).
  • 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.

  8.

  OM science parameter calculator tool
  This tool calculates for each OM exposure the:

  • total count rate
  • source count rate
  • signal to noise ratio

• General

  1.

  Assign telemetry look-up table tool
  This tool, using the telemetry bandwidths calculated for each instrument, identifies a telemetry allocation table for the observation.

  2.

  View PHS tools information file
  This tool allows the Proposal Handler to view the information file.

For a more detailed, technical description of the tools listed above, we refer to the PHS Specific Software Requirement Document.