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The beamline

How FXI's areas relate. The beam runs left to right, source to detector, through three stages plus the cross-cutting controls and resources.

FXI is a full-field transmission X-ray microscope: the condenser floods the sample with monochromatic beam, the sample sits on a rotating stage for tomography, and a zone plate magnifies the transmitted image onto a scintillator-relay camera. The structure is the same as the APS 2-BM pilot, with NSLS-II hardware and the diffractive TXM optics that 2-BM does not carry.

The areas

        18-IDA (optics hutch)                 18-IDB (experiment hutch)
  +-----------------------------+   +--------------------------------------------+
  |  Source -> DCM -> mirrors   |   |  condenser -> sample(+rotary) -> zone plate |
  |  -> white-beam slit         |-->|  -> phase ring -> Bertrand lens             |
  |  -> filters -> flux monitors|   |  -> scintillator -> detector rails -> camera|
  +-----------------------------+   +--------------------------------------------+
        SOURCE stage                      SAMPLE stage        DETECTION stage

  Controls (cross-cutting): Zebra position-capture trigger + motion controllers
  Resources: photon beam, cooling water, vacuum, liquid nitrogen (DCM cooling)
  • Source: the insertion-device source and the optics hutch (18-IDA). The double-crystal monochromator sets the energy, two mirrors steer and shape the beam, a white-beam slit defines it, attenuating filters trim flux, and three flux monitors diagnose it. Rendered as the generated source-stage device walk from the descriptor.
  • Sample: the experiment hutch (18-IDB) sample side. The TXM sample stage places and rotates the specimen; the condenser, aperture, zone plate, phase ring, and Bertrand lens are the transmission-microscopy optics around it.
  • Detector: the imaging detector. A scintillator converts the transmitted beam to visible light, the detector support rails set the propagation distance, and a camera records the magnified image.

Cutting across all three:

  • Controls: the Zebra FPGA position-capture box that hardware-triggers the camera off the rotary encoder (the NSLS-II analog of 2-BM's Aerotech PSO), and the motion controllers that drive the stages.
  • Resources: the supplies a run draws on, tracked under Operations > Supplies.

The cross-cutting reference is the Inventory: the flat Asset tree by parent_id, with the PVs and the values still pending confirmation.