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• from lclshome -> User Dev Displays panel.
• run one of the matlab scripts xalRunModel or xalGetModel.
  • xalRunModel
    • Select a beamline:
      

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• • • For example. Select "Cathode to Dump." This runs the LCLS "Full Machine" model, from the LCLS Cathode to the main Dump.

    • Wiki Markup

      Select whether to " Run extant machine or design model? (x/d) \[d\]: ". Running the "design" model (choice "d") causes the XAL model to be run with the element setpoint values in the model input files. Those design setpoint values are, to the extent possible, identical to the MAD design. Running the "extant" model (choice "x") will cause the model execution to first replace the design values of beamline devices, with the actual readback values, as acquired through EPICS, prior to running the envelope tracker. That is, "extant" is equivalent to what was called "DATABASE" in the SLC modelling system, it describes the extant machine at the time the model is run.

  • xalGetModel

Model Notes

Why are all models from Cathode to some location?

Note that all models require the model to be run from the Cathode to some beam destination, rather than allowing sections to be run independently. This is so that, for now, we can guarantee that physics computations carried out from a number of different devices throughout the machine, are carried out from consistent models made from the same initial conditions. With this technique all devices towards the photon end of the machine, must have been modeled by a model run that incorporated upstream devices. A simple example being Rmat A to B from a corrector in the injection line, to a BPM in the

Differences between XAL and MAD models.

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