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Sample

The focusing optics that form the nano-spot and the sample stack rastered through it. PVs verified against startup/13-mll.py and 15-zp.py.

HXN focuses the beam to a nano-spot two ways, and scans the sample through it. This scanning geometry, the sample axes are the measurement, is what distinguishes HXN from the full-field FXI.

The two focusing optics

Optic Family What it does
ZonePlate ZonePlate a circular Fresnel zone plate focusing in 2D as one element
MLL_Vertical / MLL_Horizontal MultilayerLaueLens (loose) a crossed pair of 1D linear-zone lenses giving 2D focus

The multilayer Laue lens binds a loose family name (MultilayerLaueLens): HXN is its only sighting, and it is geometrically distinct from the ZonePlate (1D linear vs 2D circular, run as a crossed vmll + hmll pair), so it is not folded into ZonePlate. It graduates into the catalog only at a second sighting (OPTIC-3). Whether both optics are permanently installed and operator-selected, or one is decommissioned, is a staff question (OPTIC-1).

Each optic carries an order-sorting aperture (ZonePlateAperture, MLLAperture, both Aperture) and the zone plate a central beam stop (ZonePlateBeamStop, BeamStop) to clean the focus.

The sample stack

Asset Family Axes / PV Role
SampleStage LinearStage ssx/ssy/ssz on XF:03IDC-ES{Ppmac:1} the fine raster axes (the scan trajectory)
SampleRotary RotaryStage sth on XF:03IDC-ES{ANC350:1-Ax:0} tomographic rotation
SamplePod Hexapod XF:03IDC-ES (SmarAct Smarpod) 6-DOF coarse pod

The fine ssx/ssy/ssz axes (on the Power PMAC) are what a 2D fly-scan map drives, hardware-gated point by point by the Zebra. Coarse positioning sits on the Attocube ANC350 controllers. SampleRotary combined with the raster gives nano-tomography. The SmarAct Smarpod reuses the Hexapod Family as a single coordinated parallel-kinematics move, pending confirmation that the fit holds (STAGE-2).