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The beamline

The part of 13-ID-D CORA models today, as areas you can jump to: the shared 13-ID-A optics spine, the diamond anvil cell sample environment, and the detection chain, plus the controls. First cut.

13-ID-D is the GSECARS (GeoSoilEnviroCARS) high-pressure beamline at APS sector 13. It runs monochromatic powder and single-crystal X-ray diffraction on a sample held in a diamond anvil cell (DAC) under extreme pressure and double-sided laser heating. It is CORA's first extreme-conditions (high-pressure) sample-environment deployment, the axis the EMA scout flagged. The defining instrument is the diamond anvil cell itself: the cell sets the pressure, the heating lasers raise the temperature, and the diffraction spine reads the structure that results. Its root Asset is 13-ID-D, tier Unit, facility code aps.

Two enclosures carry the beamline, grouping pending (ENC-1): the shared 13-ID-optics zone (the 13-ID-A first optics, common to the sector) and the 13-ID-D endstation. A Koyo laser-safety PLC adds a laser-emission permit axis over the endstation, carried as an Enclosure permit, not a device (LASER-1, PSS-1). The PV zones group by IOC and controller: 13IDA: (the shared 13-ID-A monochromator), 13IDE:En (the derived beamline energy), 13IDD: (the endstation devices), 13IDD_PACE5000:PC1: (the membrane gas controller), 13IDD:Laser1 / 13IDD:Laser2 (the heating lasers), 13IDDLF1: (the metrology spectrometer), 13EIG2_9M: and 13PIL1MCdTe: / 13PIL1MSi: (the area detectors), and 13IDD_Dante1: (the fluorescence MCA).

The model is reverse-engineered from the GSECARS EPICS support tree (github.com/CARS-UChicago/GSECARS-EPICS): the iocBoot startup scripts, the CARSApp device templates, and the MEDM operator screens. This is an EPICS-native source, not a dodal or BITS Python roster, so the device-to-PV reconstruction is rougher and is carried at medium confidence (see Model).

Along the beam, in order, sit the stations: the Source that delivers, conditions, and energy-selects the incident beam, the Sample that holds the specimen in the diamond anvil cell and conditions its pressure and temperature, and the Detector that records what diffracts and fluoresces. Cutting across them are the Controls. The stations are containment trees of apparatus (Asset.parent_id); controls relate to that apparatus sideways, by controller_id.

Stations

  • Source: the storage ring machine state, observe-only through a loose StorageRing (MACHINE-1); the shared 13-ID-A Si double-crystal monochromator at 13IDA:, undulator-tracked, binding Monochromator (MONO-1); the derived beamline energy at 13IDE:En, a PseudoAxis over the monochromator (MONO-1); the K-B mirror pair and carbon focusing mirrors binding Mirror, with curvature and ellipticity carried as a PseudoAxis (OPT-1); the beam-defining slits and the DAC table-top slits (DACV / DACH) binding Slit (OPT-2); the clean-up pinhole with its X/Y/Z carriers binding Aperture, the carriers LinearStage (APERTURE-1); and the attenuator at 13IDD:filter: binding Filter, the 2-BM precedent (ATTN-1). This page is generated from the descriptor.
  • Sample: the diamond anvil cell, the PressureCell that is the defining instrument here (one new loose family at n=1, HP-1); the DAC positioning stage, a micro-diffractometer binding Goniometer, and the DAC lift table binding Table (SAMPLE-1); and the cell's in-situ pressure and temperature metrology spectrometer binding Camera (HP-1).
  • Detector: the Eiger2 X 9M area detector at 13EIG2_9M:, with the Pilatus 1M CdTe / Si as alternatives, binding Camera (DET-1); the detector table and 2theta arm binding LinearStage plus TiltStage, with the 2theta swing transform deferred rather than invented (DET-1); the ion-chamber and photodiode flux monitors binding FluxMonitor (DET-1); the XGLab Dante MCA at 13IDD_Dante1: binding EnergyDispersiveSpectrometer, the 2-ID / 7-BM precedent (DET-1); and the fibre sample illumination binding a loose Backlight (DET-1).

Shared

  • Controls: the APS EPICS control stack, the same floor as the other APS beamlines. GSECARS drives it with EPICS plus SPEC plus Python orchestration, the layer CORA's edge conducts over and replaces. CORA observes the floor and does not replace EPICS. The device handles are bound from the GSECARS EPICS support tree and carried at medium confidence (CTRL-1).
  • Resources: the continuously-available supplies a run needs (the photon beam, cooling water, vacuum, and the process gas the membrane pressure system draws on), carried in the descriptor (SUP-1).

Reference

  • Inventory: the full planned CORA Asset model (every device by parent_id, with Families and pending confirmations), including the one loose PressureCell family held at n=1. That family is the only new device class on the beamline; it presents the Regulator Role for the membrane gas pressure, with double-sided laser heating and in-situ pressure / temperature metrology carried as its capabilities rather than separate families. It graduates at a rule-of-three (HPCAT 16-ID, the 13-BM-D large-volume press, the 4-ID cell), and until then the high-pressure novelty stays localized to the sample environment (HP-1, PRESSURE-1).