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Detector

The DECTRIS Eiger and its support, the on-axis viewing, and the beam diagnostics. PVs / interfaces verified against mx3_beamline_library/devices/{detectors,motors,beam}.py.

MX3's measurement is the rotation series of diffraction frames the Eiger reads as the crystal oscillates.

Asset Family PV / interface Role
EigerDetector Camera SIMPLON REST (no PV) the rotation-MX area detector
DetectorStage LinearStage MX3STG03MOT04 sets the sample-to-detector distance
FluxMonitor FluxMonitor MX3FLUXIOC:FLUX incident-flux normalization
BeamPositionMonitor BeamPositionMonitor (loose) MX3DAQIOC04: beam position + closed-loop steering
OAVCamera Camera MX3MD3ZOOM0 on-axis viewing for centring

The Eiger over SIMPLON REST

The EigerDetector is a DECTRIS Eiger (16M / 4M). Unlike every prior deployment's detector, it is not an EPICS area-detector: it is driven over the DECTRIS SIMPLON REST API, where the acquisition lifecycle maps onto HTTP requests (arm / trigger / disarm and per-key config under /detector/api/1.8.0/). It reuses the Camera family, the new REST control plane is a ControlPort seam, not a new device shape, so it carries no PV; the endpoint base is deployment config (DET-1). The DetectorStage (an EPICS Power Brick stage) sets the sample-to-detector distance, read back at MX3ES01:SAMPLE_DETECTOR_DISTANCE.

Diagnostics

The FluxMonitor reads incident flux for normalization (reuses FluxMonitor, graduated in #353). The BeamPositionMonitor pairs a beam-position monitor with a closed-loop PID steering DAC; the position-monitor half binds the loose BeamPositionMonitor family (held, DIAG-1), while the PID beam-steering controller fits no existing family cleanly and is a deferred new-device question (STEER-1). The OAVCamera (an EPICS BlackFly at the MD3 zoom optic) serves sample centring; an MD3 coaxial camera also streams over Redis.

Reuse, not new vocabulary

The detector chain needs no new Family: the Eiger and the OAV reuse Camera, the distance stage LinearStage, the flux monitor FluxMonitor. The deployment's novelty is the Site and the heterogeneous control plane, not its device families; the SIMPLON-REST detector is the clearest instance of that, the same Camera Role reached over a new transport.