Set B-station slits for alignment

Warning

STATUS: STUB. Placeholder for the procedure that satisfies the precondition b_slits_configured of Detector Z-rail alignment to the beam (detector_z_rail_alignment). To be fleshed out as the procedure is implemented.

Name

set_b_slits

Source

Not yet implemented. Future location: procedures/set_b_slits.py in the 2bm-procedures repository.

Devices

Beamline components: B-station slits — blade motors 2bma:m9 / m10 (vertical pair) and 2bma:m11 / m12 (horizontal pair). Composite Size / Centre PVs may not be published; drive blades directly and derive size = blade₁ − blade₂ and centre = (blade₁ + blade₂) / 2.

Preconditions

Enable beamline for beam (enable_beamline).
Set energy to preselect (set_energy_to_preselect) — the slit-centre Y is energy-dependent (DMM offsets the beam vertically).

Parameters

size_h_mm (number > 0) — horizontal aperture. Default for detector_z_rail_alignment: 1.0 mm.
size_v_mm (number > 0) — vertical aperture. Default: 1.0 mm.
center_v_mm (number) — vertical centre, energy-dependent. Read from energy-package lookup. Default: TBD.
center_h_mm (number, optional) — horizontal centre. Default: current value (don’t re-centre).

Steps

TBD. Compute blade targets from size + centre; drive each blade; wait for all four DMOV.

Postconditions

Satisfies:: b_slits_configured
Predicate:: |2bma:m12 - 2bma:m11 - size_h| < ε, |2bma:m9 - 2bma:m10 - size_v| < ε, centre PVs likewise within tolerance.

Failure modes

One or more blades does not reach target — check motor faults on 2bma:m9–m12 motor records.