Sample¶
The experiment-hutch sample side: the diffractometer, the sample-array stage, the pinhole, and the sample environment. PVs verified against startup/10-motors.py and startup/11-temperature-controller.py.
XPD places a powder or capillary sample in the high-energy beam and records its diffraction or total-scattering pattern. Much of XPD's science is in the sample environment: the same powder measured across a temperature ramp is how phase transitions and thermal structure are studied.
| Asset | Family | PV | What it does |
|---|---|---|---|
SampleStage |
LinearStage | XF:28IDC-ES:1{Dif:1} |
holds the sample and the detector arm |
SampleArrayStage |
LinearStage | XF:28IDC-ES:1{SampArray} |
presents many samples for high throughput |
Pinhole |
Aperture | XF:28IDC-ES:1{PinHole:XRD} |
cleans the beam onto the sample |
SampleTemperature |
TemperatureController | XF:28IDC-ES:1{CS:800} |
cryostream / furnace thermal environment |
The diffractometer and sample stages¶
The SampleStage is the diffractometer (Dif:1: theta, X, Y, and inboard/outboard two-theta) that holds the sample and the detector arm. CORA binds it to LinearStage as a design-phase placeholder; the diffractometer carries goniometric (rotation) axes, so whether its orientation is modelled as a Goniometer plus a Diffractometer Assembly, the shape Diamond I11 and APS 8-ID use, is folded into STAGE-1. The SampleArrayStage presents many samples in a row for unattended high-throughput acquisition, fed by the sample-changing robot (ROBOT-1). The Pinhole cleans the beam onto the sample, reusing the Aperture family.
Sample environment¶
XPD carries a rich sample-environment cluster: the cs700 and cs800 cryostream controllers (understood to be Oxford Cryostreams, an inference pending TEMP-1), Eurotherm and hot-air blowers, a Lakeshore cryostat, and a Linkam furnace. CORA models them as one SampleTemperature Asset (the cryostream is canonical) and reuses the TemperatureController family, the same Family Diamond I11 graduated for exactly this, variable-temperature powder diffraction (TEMP-1). This is the reuse point: the continuous-setpoint thermal actuator that earns its keep at a powder beamline is the same one that serves spectroscopy (BMM) and coherence (CHX). Which units are live is TEMP-1.