Sample¶
The endstation sample side: the KB nanofocus that forms the coherent spot, the beam-conditioning unit, the sample goniometer, the positioning towers, and the endstation diagnostics. PVs verified against cditools/motors.py (KB / BCU / GON classes), startup/18-screens.py, 21-tdms.py, 31-electrometers.py.
CDI focuses the coherent beam to a small spot with a Kirkpatrick-Baez mirror pair, conditions it through the beam-conditioning unit just before the sample, and records the far-field diffraction pattern. The sample side carries the focusing optic, the goniometer, and the endstation positioning towers; the real-space image is recovered offline by phase retrieval, a ComputePort leg, not modelled here.
| Asset | Family | PV | What it does |
|---|---|---|---|
KBMirror |
Mirror | XF:09IDC-OP:1{Mir:KBv} |
KB nanofocus pair (VKB + HKB) forming the coherent spot |
ConditioningSlit |
Slit | XF:09IDC-OP:1{Slt:BCUU} |
beam-conditioning-unit slits trimming the beam at the sample |
InlineCamera |
Camera | XF:09IDC-BI{BCU-Cam:9} |
BCU inline beam-viewing camera |
Goniometer |
Goniometer | XF:09IDC-OP:1{Gon:1} |
sample goniometer and stack |
SampleTower1 |
LinearStage | XF:09IDC-ES:1{TDMS:T1} |
endstation positioning tower 1 |
SampleTower2 |
LinearStage | XF:09IDC-ES:1{TDMS:T2} |
endstation positioning tower 2 |
DiamondBeamMonitor |
BeamPositionMonitor (loose) | XF:09IDC-BI{BPM:1} |
transmissive diamond BPM ahead of the sample |
SampleCamera |
Camera | XF:09IDC-BI{SMPL-Cam:10} |
sample-viewing camera |
Forming and conditioning the coherent spot¶
The KBMirror is the focusing optic that makes CDI a nanofocus beamline: a vertical mirror (VKB) and a horizontal mirror (HKB) in the Kirkpatrick-Baez crossed geometry, each with pitch, roll, and yaw plus jack and translation axes, a defining slit, and a fluorescent screen, with an exit window after the pair. It focuses the coherent beam to the small spot the imaging needs, and reuses the Mirror family, the same binding the FMX and SRX KB mirrors carry; the focal size and coating are KB-1.
The ConditioningSlit is the beam-conditioning unit (BCU): an upstream slit pair and a downstream slit pair that trim and guard the coherent beam just before the sample, with an InlineCamera on the same module for beam viewing. For a coherent-imaging beamline these slits are the coherence-conditioning hardware, so CORA models them as first-class Slit Assets rather than folding them into settings.
The sample stack¶
The Goniometer is the sample goniometer and stack (Gon:1): sample lab-frame translations and rotations, with small-sample and large-sample axis sets and alignment axes, plus a sample-viewing screen. It reuses the Goniometer family; the orientation axes matter for Bragg CDI, where the sample is rocked around a Bragg peak. The full axis set is STAGE-1.
The SampleTower1 and SampleTower2 are the two endstation positioning towers (the source's TDMS towers), each carrying translation, camera, and angle axes. Which tower carries the sample and which carries the detector, and the sample-to-detector distance that sets the recorded q-range, are not settled in the public config (some tower axes are read-only pending commissioning), so they are folded into STAGE-1. Both reuse the LinearStage family.
Endstation diagnostics¶
The DiamondBeamMonitor is a transmissive diamond beam-position monitor read through a TetrAMM electrometer, just ahead of the sample; in source it was repurposed from ion-chamber use to the diamond BPM. It binds the loose BeamPositionMonitor family (held; DIAG-1). The SampleCamera views the sample on-axis (a further endstation Prosilica sits alongside); it reuses Camera, and the live diagnostic set is CAM-1.