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Optics and endstation

The MFX-hutch beam conditioning, the pump-probe laser, the sample delivery, and the emission spectrometer. Design-phase, with the pcdshub-derived handles recorded.

The MFX experiment hutch is where the transported beam is conditioned to its final state and meets the sample. This is the stage that most exercises the family-fold finding: every conditioning device folds into an existing Family, and the one device that did not (the emission spectrometer) introduced the EmissionSpectrometer family, since graduated into the catalog once ISS earned the second sighting.

Conditioning the beam

  • Pulse picker (MFX:DIA:MMS:07): a fast single-pulse selector. It folds into the Shutter Family as a fast beam gate; whether a rotary pulse-picking chopper deserves its own Family (the loose Chopper shape) is open (PULSE-1).
  • Attenuator (MFX:ATT): a solid-Si binary attenuator. The Filter Family covers the discrete foil selection. What it does not cover is the AttBase solver that picks a foil combination for a requested transmission, energy-dependent; that is the deferred Attenuable leg, and MFX is its rule-of-three trigger (ATT-1).
  • DCCM: a diamond double-channel-cut monochromator for monochromatic and spectroscopy modes; MFX also runs pink / SASE beam with the mono out. It folds into Monochromator; the crystal details and the pink-vs-mono mode boundary are carried confirm (MONO-1).
  • Transfocator and prefocus (MFX:LENS, MFX:DIA:XFLS): compound-refractive-lens (beryllium) stacks that focus the beam. They reuse the graduated Transfocator catalog Family (a CRL focusing optic), also bound at I22 / 4-ID / 8-ID. Selecting a lens set for a target focal length is a solver with the same shape as the attenuator (ATT-1).
  • Slits (MFX:DG1:JAWS, MFX:DG2:JAWS:*) and profile imagers (MFX:DG1:PIM): standard 4-blade slits (Slit) and YAG-screen imagers (Scintillator + Camera).

Per-shot diagnostics

  • Intensity-position monitors (MFX:DG1:IPM and siblings): each reads both flux and beam position per shot, presenting the Sensor Role through the loose FluxMonitor and Diagnostic families (DIAG-1). Per-shot intensity normalization (dividing each pattern by its incident pulse intensity) is a DAQ-plane concern, not a CORA observation row (DAQ-1).
  • Wave8 (MFX:DG1:MMS:08): a fast per-shot intensity / wavefront diagnostic; loose FluxMonitor.
  • Timetool / arrival-time monitor (MFX:ATM): measures the X-ray-to-optical-laser timing jitter shot by shot. It presents the Sensor Role (loose Diagnostic), but its reason for existing is to drift-correct the pump-probe delay, a cross-timing-domain relationship CORA has no model for (LASER-1).

The pump-probe laser

The femtosecond optical laser (LAS:FS45 timing, MFX:LAS:MMN:* motors) excites the sample before the X-ray probe. The laser device folds into the loose Laser family (the 4-ID POLAR precedent, model-vs-hazard open), and the delay stage is a LinearStage. What does not fold is the synchronization: the lxt_ttc SyncAxis holds the laser and FEL timing domains together to within a ~50 fs deadband, a cross-timing-domain relationship CORA's single-domain PartitionRule cannot express (LASER-1). The laser is also a class-4 hazard gated by a Clearance (see Governance).

The interaction point

  • Sample delivery (MFX:LJH): a Beckhoff-controlled liquid jet (and a fixed-target option) streams microcrystals into the beam for serial crystallography. Sample delivery is endstation-specific with no storage-ring analog; it is carried with its shape and the Subject custody lifecycle deferred, and no Family is coined (SAMPLE-1), mirroring how I03 carries its sample-exchange arm.
  • Von Hamos emission spectrometer (MFX:SPEC): a 6-crystal X-ray emission spectrometer for XES and HERFD. A crystal-analyzer dispersive spectrometer that composes analyzer crystals and a 2D detector along a dispersive geometry, structurally distinct from a Monochromator. It introduced the EmissionSpectrometer family, which GRADUATED into the catalog once NSLS-II ISS (8-ID) earned the second sighting (its Johann + von Hamos XES / HERFD spectrometers); MAX IV Balder (the SCANIA-2D spectrometer) is a third near-sighting. Whether each analyzer crystal is a child Asset is the residual question (SPEC-1).

See the Detector page for how the recorded shots leave the hutch, and Open questions for the conditioning and endstation items still to confirm.