Week 43 · Oct 19–23, 2026

Oct 19–23, 2026

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Summary for Hall-B

HTCC cone repairs, plus the Moller cone and all beamline fixed
DC CAD support moved to DC
Big CAD mesh-sharing pass on magnets: vacuum jackets, DC supports/membranes, hub shields, torus coils — large facet reductions
OSG queue fairness fix (all 25 tests pass), threshold restored to 80,000
NERSC AY2026 allocation requested
GEMC3 Python environment reworked: centralized in pygemc, 3.10–3.14 support, Homebrew-upgrade resilience
New GEMC3 viewer/UI: XR visualization + export, multi-volume Space Bar toggle

GEMC

Verified all HTCC variants; recorded the cured entry cone’s residual contact with its entry window, and synchronized the three cured HTCC cone meshes (originals archived, remaining topology limits noted).
Repaired the HTCC Moller cone in both engines, retaining its bore and bounds in a 6,902-facet mesh.
Updated the CAD optimization note with HTCC cone repairs, validation evidence, and unresolved contacts.
Magnet CAD sharing/optimization pass (geometry unchanged, names preserved where noted):
- Renamed all magnet shell placements and STL sources to vacuum jackets in both engines; shared compatible jackets while keeping all holes, cutting unique facets by 48.86%. Verified jacket names across both engines and three runs with identical mesh geometry.
- Shared and moved six DC supports out of magnets (6,036 → 1,006 unique facets) and six DC back membranes out of magnets, sharing one mesh (120 → 20).
- Optimized the separate upstream and downstream magnet plates and jackets with filled fastener holes and retained rims/names.
- Removed duplicate downstream and apex shielding from magnets in all three configurations.
Hub/coil sharing in both engines:
- Renamed the bore center tube, retaining all 1,130 facets to preserve profiles and holes.
- Renamed and repaired the cold hub, keeping every opening (12,600 → 12,548 facets).
- Shared five hub shields preserving both different ends and all holes (4,146 → 1,594), and six renamed hub covers through two unchanged meshes (348 → 162).
- Shared all six torus coils while retaining every opening (6,096 → 1,016 unique facets).
Clarified the GEMC introduction with Python prerequisites and runtime database loading; preserved highlights.

OSG

Fixed OSG queue fairness across recalculations and counted running plus idle jobs; all 25 tests pass.
Restored the OSG submission threshold to 80,000 for production and development; verified both modes.
Submitted an AY2026 application for 250 node hours @NERSC (through January 2027) to check feasibility of running simulation jobs there in addition to OSG.

Geant4

macOS prerequisites/installer work:
- Restored the original macOS prerequisites and documented mixed Homebrew, MacPorts, and SDK discovery.
- Documented macOS ICU prerequisites and CMake discovery for Xerces-C builds, noting the ICU location override is optional when automatic discovery works.
- Disabled installer colors outside capable terminals and verified CI-style initialization.

GEMC3

Validation runs for the CAD sharing pass (no new overlap pairs; startup ratios recorded):
- Jacket copies 1.17×; rounded DC positions to three decimals in both engines; support angles 1.62×; DC angles 1.79×.
- Ported the solenoid and all magnets CAD unchanged with passive placements and three validated runs.
- Upstream magnet names/spacing preserved; separate magnet plate and jacket volumes retained; ten duplicate magnet meshes removed — all with recorded facet/timing/tracking checks.
- Bore tube: nine construction checks and semantic comparisons passed, clearances unchanged. ColdHub 1.161×, hub shields 1.402×, hub covers 1.000×, coils 1.401×.
- HTCC: cleared solid warnings in nine construction checks, retained matching native and CAD geometry.
Python environment rework:
- Pinned macOS packaging to Python 3.12 with an early pymeshlab wheel check; later replaced the cutoff with explicit interpreter selection after verifying Python 3.14, then restricted support to 3.10–3.14 with mesh dependencies mandatory and both environments aligned.
- Added a Python 3.12 fallback plus environment backups to survive Homebrew upgrades.
- Centralized Python environment installation in pygemc, removed the GEMC and CLAS12 duplicates, and documented local latest/dev pygemc install modes in the README (GEMC build hook unchanged).
Viewer / UI:
- Fixed experiment generation to collect HTCC geometry and CAD meshes with all implemented detectors.
- Fixed option search to include detailed help, schema metadata, and defaults; verified viewer discovery.
- Added Space to toggle the selected volumes-tree row visibility (mouse checkbox behavior preserved), enabled multiple volume selection, and Space to hide/show the group together.
- Enabled logical-overlap drawing within selected volumes, updated the label/translations, and used OpenGL to avoid the ToolsSG rendering crash.
- Added Physics controls for list selection, production cuts, process activation, and optical switching tests.
- Enabled optional Geant4 XR visualization and added an XR Server button to Display Utilities to open XR and export one event with rich tracks; refreshed flags after Geant4 rebuilds.
Fixed repeated Qt header warnings by treating Geant4 core dependency includes as system headers.

Actions

Fixed website updates to skip an unconfigured pygemc milestone and continue CLAS12 release-note updates.

Publications

Added evidence for the CAD optimization work: jacket hole preservation and facet counts; support-copy and DC copy evidence with dense overlap checks and tracking ratios (0.977–1.041, 0.985–0.997); upstream and separate magnet plate/jacket metrics with material changes; magnets shielding removal with repeated benchmarks.
Documented the bore-tube audit (zero facet reduction, no established speedup), cold-hub repair, hub-shield and hub-cover mesh verification (timings, memory metrics, overlap checks), and coil shape verification.
Documented the HTCC seam repair: restored conical wall, retained profiles, and validation limits.