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The energy-selecting turbo slit, the trajectory PMAC, the PandA timing, and the seam between CORA and the floor. These are the EDE periphery the commissioning module does model.

Selecting energy from the dispersed fan: the turbo slit

In full EDE the strip detector reads the whole energy band at once. The TurboSlit (BL51P-OP-PCHRO-01:TS:) is the device that, for alignment or single-energy work, picks one energy out of the polychromatic fan: its xfine axis is the main scanning axis (energy), gap sets the energy resolution, and arc is the coarse gap-centre. It reuses the Slit family; the EnergyAxis is its xfine selection. The bent-crystal polychromator that produces the fan it selects from is the open question POLY-1.

The fly-scan: PMAC trajectory + PandA timing

The turbo-slit xfine axis is swept by a TurboSlitController, a PMAC trajectory controller (BL51P-MO-STEP-06:) running a trajectory program over its coordinate system, reused as a MotionController. Two PandA FPGA boxes (Timing, BL51P-EA-PANDA-02: and -PANDA-01:) provide the hardware triggering and position capture that synchronize the sweep with the detector, reused as a TimingController. This trajectory-plus-position-capture fly-scan is the same hardware-orchestration shape CORA drives at the other beamlines (the Zebra / PandA pattern), here applied to the energy-selecting slit.

The seam: CORA and the floor

This is where CORA's design meets the I20-1 floor. The shape matches the other dodal-modelled Diamond beamlines'.

CORA owns (its conducting engine, over the ControlPort):

  • the EDE acquisition: arming the strip detector (when modelled), driving the turbo-slit / PMAC fly-scan for energy selection or alignment, and reading the detector through the time series;
  • the choice of technique and timing, gated by the trust boundary.

CORA drives through (the floor it actuates and observes, and does not replace):

  • the EPICS IOCs via the ophyd-async device layer (dodal): the turbo slit, the PMAC, the PandAs, the sample stage, the Xspress3, the ControlPort boundary;
  • the polychromator crystal and the strip detector, once they are PV-bound (POLY-1 / STRIP-1);
  • the facility filestore where the per-shot spectra land. CORA moves them, over the TransferPort, into CORA's own Dataset of record.

So CORA brings one conducting engine to I20-1, working over the ports: the EDE fly-scan over the ControlPort, the spectrum extraction (the dispersed-frame to absorption-spectrum reduction) over the ComputePort, and data egress over the TransferPort. The reduction is a clean ComputePort leg, the dispersive analogue of the reconstruction legs at the imaging beamlines.

The software interfaces (PandA, PMAC, Xspress3) are referenced by interface only, never registered as Assets.