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The fast-shutter-gated acquisition, the motion controllers, and the seam between CORA and the floor.

Triggering: the fast shutter

SMI does not use a hardware position-capture box. Its Pilatus detectors run in software-triggered modes, gated by the endstation fast shutter (FastShutter, XF:12IDC-ES:2{PSh:ES}, a piezo open/close with a backing Y motor); a scattering measurement is a held exposure on both detectors at once. The exact acquisition modes are part of the recipe layer (deferred at this design phase).

Motion controllers

The sample, detector, and beamstop axes are driven by endstation motion controllers (SmarAct MCS, MDrive, and Thorlabs units are named in source); their box models, firmware, and IPs are not fully in the profile collection (DRIVE-1), so EndstationMotionController is carried as a MotionController family with the specifics blank.

The seam: CORA and the floor

This is where CORA's design meets the SMI floor. The shape matches the other NSLS-II beamlines'.

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

  • the acquisition: positioning the sample (including the grazing-incidence angle), setting the SAXS camera length and the WAXS arc, and collecting the two Pilatus frames under the gated exposure;
  • the choice of technique, detectors, camera length, and in-situ environment program, gated by the trust boundary.

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

  • the EPICS IOCs via the ophyd hardware abstraction: the ControlPort boundary;
  • the coupled energy pseudopositioner (undulator gap plus DCM), the mirror benders, the CRL transfocator, the WAXS-chamber vacuum automation, the PSS interlock, and the Pilatus detector IOCs;
  • the facility filestore where the per-run frames land. CORA moves them, over the TransferPort, into CORA's own Dataset of record.

So CORA brings one conducting engine to SMI, working over the ports: scattering acquisition over the ControlPort, the azimuthal integration and reduction (the SAXS / WAXS / GISAXS data reduction) over the ComputePort, and data egress over the TransferPort into the CORA Dataset. The reduction is a clean ComputePort leg, the scattering analogue of the reconstruction legs at the imaging beamlines.

The software IOCs (Pilatus, Amptek, TetrAMM, Prosilica, Linkam, LakeShore, the SmarAct controllers, the blade coater) are referenced by PV namespace only, never registered as Assets.