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ESM

The Electron Spectro-Microscopy beamline at NSLS-II, and CORA's third soft X-ray deployment, the first photoemission one. This page walks the ARPES branch CORA models today. It is a reverse-engineered first cut, not yet a running model.

Property Value
Asset ESM (root Asset, tier = Unit, parent_id = None)
Facility NSLS-II (bound via facility_code = "nsls2", FacilityKind = Site)
Sector Sector 21 (PV namespace XF:21ID*; not a registered Asset)
Status First cut, reverse-engineered, design-phase (ARPES branch; XPEEM/LEEM deferred)
Source Two elliptically-polarizing undulators (EPU57, EPU105) on the SR:C21-ID straight
Control stack NSLS-II EPICS / ophyd (the same floor as the other NSLS-II beamlines); handles bound from the profile collection, carried confirm

First cut, and confirm-pending by intent

This scaffold was reverse-engineered from the beamline's own bluesky profile collection (NSLS2/esm-arpes-profile-collection). EPICS PVs are real and verified against the startup/*.py files; vendor part numbers, serials, and physical positions are not in the profile collection and are open questions. Every value is carried as confirm until ESM staff verify it. What CORA needs the team to confirm is on Open questions.

What makes ESM different

ESM is CORA's first photoemission beamline. Every prior beamline measures photons; ESM measures electrons (photon-in / electron-out), which brings a new detector regime:

  • A hemispherical electron analyzer. The Scienta SES records electron counts over a kinetic-energy by emission-angle window set by the pass energy and lens mode. No photon-detector Family fits, so it binds the ElectronAnalyzer Family (presents the Detector Role), which graduated once SST earned the 2nd Scienta SES.

It is also a consolidation of the soft X-ray regime:

  • Reuses the graduated GratingMonochromator. ESM's PGM is the third soft X-ray plane-grating monochromator (after SIX and CSX), so it binds the catalog Family rather than minting one.
  • Graduates Manipulator. ESM's LT six-axis UHV cryostat manipulator is the second UHV sample manipulator after SIX, earning the abstraction (two-deployment threshold): Manipulator becomes a catalog Family in this deployment, and SIX's references are swept loose to graduated (see Model).

Scope: what is and is not modelled

Part In this cut Why
Optics (XF:21IDA/B/C) Yes Two EPUs, M1, the PGM, M3, the KB pair M4A, M4B, the slits and exit slits
ARPES endstation (XF:21ID1-ES) Yes The UHV cryostat manipulator, the SES electron analyzer, the flux monitors
Manipulator Graduated The 2nd UHV manipulator earns it into the catalog (see Model)
XPEEM/LEEM branch (21-ID-2) No The LEEM/PEEM electron microscope is a future loose ElectronMicroscope Family (PEEM-1)
Sample-prep / load-lock transfer No The prep / analysis-chamber manipulators and the load-lock claw are deferred (SAMPLE-1)

The deferred parts are recorded on Model.

The beamline

  • Source: the generated device walk: the two EPUs, M1 and the polarization diagnostic, the PGM and M3, and the KB refocusing pair, M4B, and the exit slits.
  • Sample: the ARPES UHV cryostat sample manipulator and the cryostat temperature controller.
  • Detector: the hemispherical electron analyzer and the beam-current flux monitors.

Cutting across them:

  • Controls: the EPICS / ophyd control stack and the bluesky-orchestration seam; handles bound from the profile collection and carried confirm.

The cross-cutting reference view is the Inventory. The Source page is generated from the beamline.yaml descriptor.

Techniques

Techniques: what the modelled part of ESM is designed to do, as intent. ARPES is a photoemission technique new to CORA's catalog and renders unlinked, carried pending.

Governance

Governance: who will act at ESM and the trust shape that gates their commands. People and agents are facility principals at the NSLS-II Site.

Model

Model: the developer's by-kind index, the Manipulator graduation and ElectronAnalyzer this deployment introduces, and the record of what is deliberately deferred.

Not yet documented

ESM is not yet driven by CORA, so the operations runbook and the live experiment view are deliberately not written yet. They join as the deployment firms up. The 2-BM deployment shows the shape they will take.