Action plan

Bounded research deliverable accepted; future extensions require a separate decision

Current position

M4 has its verification records, guard integration and cheap CI re-proof. ITER version 2 is packaged separately; its actual local-robustness result is 12 states proved, three unknown and five outside domain under the actual local-robustness toleranceC-326. The earlier negative proof investigation remains historical evidence (both full-box pilots retain nonfinite physical enclosures after all final objectives run; independent graph, constraint and corrected-dual replay passes, with no finite physical candidateC-297); the owner grants certification within the stated limits under OQ-52. OQ-42, OQ-45 and OQ-46 retain the stated limits. No failed proof or out-of-domain robustness box is relabelled as a pass. The guard artifact audit is all four verified input boxes match the previous loaders; 48 of 48 retained pedestal states keep identical predictions and decisions; none of the 57 EC states is inside the exact proof boxes, so no EC certificate-based output check applies thereC-284.

The full original ITER ensemble now passes the numerical convergence gate under a new continuous transport closure (all 33 original cases reach five seconds at all three maximum-step settings: 99 of 99 valid trajectories and 264 of 264 passing endpoint comparisonsC-305, the largest changes are 0.219% for coarse-to-middle and 0.0423% for middle-to-fine, both below the 1% acceptance limitC-306). The opt-in integration combines strict physical-residual solves, continuous guarded coefficients and complete rollback (the new research baseline uses a continuous guarded closure, Newton trials accepted only after residual decrease, and adaptive rollback of the complete state and auxiliary dataC-304). The result and technical protocol state its limits. Historical hard-switch ladder failures (C-295, C-296, C-298) remain historical results rather than being relabelled as passing.

The earlier uncertainty study retains its prior definitions, nonlinear flags (C-287) and calibration evidence (C-285). The complete current-baseline design and driver now use OQ-51. three selected five-second trajectories pass the raw audit; only one of ten finite-difference controls survives the derivative timeoutC-327. the 18,432-trajectory design projects roughly 1,710–1,877 node-hours in the measured worker layout, before derivatives and recoveryC-328. Full execution and complete derivative validation remain incomplete and are excluded from the accepted bounded completion scope. OQ-52 records closure acceptance and reduced-scope M5 physicist sign-off, retaining unquantified pedestal/equilibrium discrepancy (K-035). Any extension needs a separate scope/resource decision.

Accepted package and retained limitations

work	state	next decision
M4 model-bound evidence and four records	v2 packaged; robustness limitations retained	owner-approved within stated limits (OQ-52)
guard artifacts and fallback monitor	implemented; no proof box expanded; revised OQ-50 alert policy adopted	no threshold decision is outstanding
cheap CI re-proof	implemented and checked	no additional compute
hybrid calibration and Bayesian reference-label audit	computed; conditional assumptions stated	conditional assumptions retained under reduced-scope acceptance
ITER numerical baseline	full ensemble convergence passed (C-305, C-306)	frozen closure accepted (OQ-52); full UQ excluded from bounded completion
ITER Monte Carlo, linearisation and sensitivity	historical study retained	full current-baseline execution remains incomplete; separate future scope/resource decision
internal predictor/corrector diagnosis	completed with parent-trajectory parity; internal branch mismatch and a local residual contribution established	historical checkpoint protocol superseded by the passing continuous baseline
pedestal/equilibrium physical discrepancy	unquantified	accepted as unquantified within the reduced scope
public draft entries	prepared locally	owner publication decision

JOREK: finish J5, then decide its role

1. Done: the second case (b) job is analysed with the pre-registered window rule. n = 12, 16 and 20 grow at the pedestal, weakly; n = 1–8 show no measurable growth by the end (entry 73).
2. Done: the time-step check. Each of n = 12, 16 and 20 restarted from the same snapshot at Δt = 1 and Δt = 0.5; halving the step changes γ by about one part in ten thousand (entry 75). The doubled grid’s axisymmetric state is ready.
3. Incomplete: the grid check (OQ-43, the owner chose the full check). All listed chains have ended. The measured-cost projection invokes the existing stop rule; unused job slots do not permit continued links (all three selected fine-grid checks remain incomplete; the measured-cost projection exceeds the existing compute envelope and further submissions stopC-291).
4. Retain the unchanged-rule incomplete result and resource decision. Do not quote a fine-grid growth rate or infer stability from insufficient growth.
5. The owner then decides what JOREK becomes in the toolkit: a surrogate of a JOREK quantity, reference runs only, or neither. One case (b) n-scan costs about two six-hour node-jobs before any convergence check, which bears on that choice.

Decisions ahead

when	decision
guard alert policy	revised report-only thresholds already adopted under OQ-50
end of J5	JOREK’s role: surrogate, reference runs, or neither
M4 closeout	scoped certification granted under OQ-52

M5 inputs and accepted scope

OQ-47 fixes the minimal Tier A scenario, priors and quantities of interest; OQ-51 fixes current-baseline transport calibration, with OQ-48 retained for historical results and as the conservative alternative. Do not reopen those decisions to repair numerical failures. Retain the same cases and physics through temporal refinement. The new continuous baseline now supplies its declared numerical pass. The complete adopted design is implemented; its full uncertainty and sensitivity execution remains unrun. Pedestal and equilibrium discrepancy remain unquantified; marginal conformal intervals do not supply a validated final-power error bound. OQ-52 grants physicist sign-off for the bounded deliverable, with full UQ explicitly incomplete.

M3 work record

The sections below are the M3 plan as written while M3 was open. M3 closed on 10 Oct 2026 (entry 41).

Complete the performance comparison

Resolve the cancelled compute run, then agree a fresh bounded submission. Compare TGLF, the final monotone surrogate and QLKNN using matched scenario, grid and solver settings. Record compilation separately from execution, resource allocation, finite profiles, solver status, profile errors and accepted-state guard rejection. Every output carries provenance.

Profile Newton separately to distinguish ensemble inference, transport/geometry work and Jacobian construction. Keep unresolved overlap visible (K-022). Historical speed-up belongs to the original model; timings from different hosts or drivers cannot establish final-model speed-up.

Done when: a reproducible final-model runtime comparison and discrepancy report exist, with allocation and solver settings stated.

Done 10 Oct. The cancellation matched a recurring node start-up failure (seven full-node jobs since 2 Oct were cancelled by root at start with no reason; each resubmission landed on another node and ranC-161); the approved resubmission ran and gives TGLF 539.1 s, final v3 surrogate 1.249 s, QLKNN 0.117 s; the v3 surrogate is about 432 times faster than TGLF and 10.7 times slower than QLKNNC-158, with profile deviations final v3 surrogate: T_e 7.7%, T_i 9.2%, n_e 11.4%, psi 0.32%; QLKNN: T_e 155%, T_i 128%, n_e 86%, psi 2.4%C-159 (entry 35). The runner now rejects coarse-tolerance results, records effective CPU allocation, separates warm-up from execution and records final-state guard diagnostics after timing. Focused checks pass (11 performance-tool checks pass in full and Tier-A-only modesC-147). The offline saved-trace audit records unresolved component attribution (72059 complete HLO events with about 5.369 s of covered trace timeC-148); K-022 remains open.

Complete the EC and ITER pedestal contracts

The owner has selected the reference, pedestal model and EC channels in OQ-21. EC labelling and the ITER pedestal port proceed independently. The prescribed MAST-U pedestal remains, with predictive closure deferred; IC is deferred.

Complete the EC launch/current-drive prescription, power convention and coordinate/units mapping. For ITER, choose the pedestal solution and map pressure/width to supplied density, temperature and boundary conditions. Retain explicit Tier A fallbacks and acceptance criteria.

The native EC output reader preserves separate channels and SI units; its focused checks pass (24 focused tests pass in full and Tier-A-only modesC-151). The original ITER deck is selected for the numerical pilot only; production launch and current-drive settings remain open.

The saved upstream ITER output also passes the reader/accounting check (200 native bins in the saved upstream ITER EC output pass reader and accounting checksC-152). The bounded pilot runner retains immutable inputs, outputs, logs and failures; its combined checks pass (40 focused pilot, reader and Tier A checks pass in full and Tier-A-only modesC-153). The external reference now builds with a replacement plotting library (one external reference executable builds with verified artifacts and resolved runtime librariesC-154). The corrected numerical pilot is complete with readable native profiles (the corrected EC reference completes in 83.16 s with readable native profilesC-156). Native accounting and descriptive saved-reference comparison are retained; the rendered PostScript page is blank. Settle the production coupling contracts and grouped sampling before reviewing a separate labelling budget.

Done when: those contracts and required access are recorded. Done 10 Oct: the owner accepted the recommended conventions (OQ-21, entry 36).

Train and integrate the response surrogates

Define physically related case groups and label a small baseline. Keep entire groups together in training and holdout sets. Inspect failed labels, sampled domains and physical integrals. After the baseline, agree held-out accuracy metrics and targets with the owner.

Train structured EC ensembles and evaluate untouched holdouts. The selected pretrained ITER pedestal is ported directly; no second network needs to learn its outputs. Integrate source and boundary responses into TORAX behind guards with Tier A fallbacks. Supply channel adapters required by the selected targets. Check gradients, finite execution, energy/particle balance, physical rejection, fallback use and coupled cost. Pointwise profile errors alone do not establish absorbed-power accuracy.

Done when: the reference datasets, checkpoints, accuracy results, guarded coupled checks and matched cost measurements have provenance and meet the agreed criteria.

EC dataset v1 is labelled (3120 of 3120 cases produce readable output (20 of 20 check cases); median 84.8 s of GENRAY time per caseC-164). The first baseline learns the totals but its pointwise profile model does not beat the training mean (driven current RMSE 3.30 kA/MW against 13.5 kA/MW for the training mean; pointwise profile model: current-density RMSE 2.20e4 A/m^2 against 2.09e4 A/m^2 for the meanC-166), so the EC model needs a structured profile output. K-028 records that every case uses one equilibrium. The owner then set the targets and restricted the states (K-028 option b); the structured surrogate meets all three targets (all three targets pass: absorbed power 0.01% and driven current 2.7% median relative error (targets 10%), heating centre 0.0036 median absolute error in rho (target 0.05)C-168, entry 38). Both the EC surrogate and the ITER pedestal now run inside TORAX behind their guards (runs under jit for both launchers with the surrogate serving the source; energy balance within 1e-6 and particles within 1e-10; derivatives through Newton match finite differences to 1e-7C-171, runs under jit with EPEDNN setting the pedestal; energy balance within 1e-6 and particles within 1e-10; derivatives through Newton match finite differences to 1e-7C-173, entry 39).

Close M3, then start M4

Audit the complete M3 criteria: held-out accuracy, differentiable guarded execution and measured end-to-end speed-up. Transport accuracy alone does not close the RF/pedestal tasks. Keep the ion-flux convention, monotonicity departure, default-root tolerance and domain limits visible (K-024, K-025, K-026).

After M3 acceptance, agree verification properties and trajectory tolerances with the owner. Prove properties over declared input boxes, calibrate uncertainty on held-out data, compare trajectories against Tier A references and prepare per-surrogate verified-domain reports. Certification review closes M4. Sampled monotonicity and raw ensemble spread are not certificates.

Keep the build log current

After each completed step, update its narrative entry, technical section, claims, ceilings, milestone state and executed statistics. Counts that reuse unchanged execution reports retain that qualification. Drafts and disclosure-held pages remain in the private review copy until the owner reviews them. The owner renders and publishes the separate website handoff.

M3 closed on 10 Oct 2026 (entry 41). The reference diagnostic is now consumed (the diagnostic completes in 517 seconds within its 30-minute bound, with 40 finite converged steps, exact historical temperature/density/poloidal-flux-profile and final-mask equality, and 171 passing saved-output integrity checksC-193). OQ-32 retains the current nonnegative contract while investigating signed heat transport (final face 4 at normalized radius 0.16 has valid inputs but raw electron heat diffusivity -0.02792124888 m²/s; negative heat diffusivity rejects that face at 8 of 40 accepted states; reference rejection is 323/1040 accepted-state face records (31.0577%)C-194), preserving reference inadmissibility and the separately proposed sampling experiment. The read-only conversion review is complete (the final electron heat flux is inferred as -0.001689376033 gB; all 9 negative channel records at 8 accepted states have outward-decreasing temperature and no denominator-epsilon sign reversal, with maximum epsilon ratio 1.03e-11; all negative magnitudes are below 1 gBC-195, 33 focused checks pass in each mode, including 14 new sign/units/history tests; all 80 native heat-converter round trips meet the mixed 1e-12 parity criterion (maximum absolute difference 8.88e-16 m²/s), 32 numerical source files match the diagnostic bindings, and all 78 source modules pass typingC-196); direct mode evidence remains unavailable from the current wrapper. The richer native route passes preparation checks (55 focused checks pass in each mode, including 22 direct-output and settings checks; all 79 source modules pass typing; the compiled synthetic writer preserves signed species heat and passes total/low-k spectral parity without calling TGLFC-197); the complete direct collection and backend discrepancies are now retained (648 integrity checks pass on the complete 15-state collection; all affected signed states agree between backends, but four control states fail the existing parity criterion; original terminal tracking failure is preserved and archive recovery calls no solverC-199). OQ-34 approves the signed reference specification. Check numerical repeatability (31 synthetic diagnostic tests pass in each mode, including archive identity and repeatability completeness/discrepancy checks; 33 unchanged focused records are retained, giving 64 focused recorded passes per modeC-200) and review the energy closure under OQ-33’s bounded-run permission. OQ-17 selects MIT for original code/documentation; publication remains separately reviewed. Continue M4 under its existing decisions (OQ-22). See M3 status, decisions and known ceilings.

Entries 21 to 34 and the active-learning and surrogates pages were approved on 9 Oct. New entries follow the same review before publication.

The complete richer collection is retained despite its terminal tracking failure (648 integrity checks pass on the complete 15-state collection; all affected signed states agree between backends, but four control states fail the existing parity criterion; original terminal tracking failure is preserved and archive recovery calls no solverC-199). OQ-34 approves a signed reference specification and staged verification. Numerical repeatability tooling passes synthetic checks (31 synthetic diagnostic tests pass in each mode, including archive identity and repeatability completeness/discrepancy checks; 33 unchanged focused records are retained, giving 64 focused recorded passes per modeC-200); reference admissibility and a stable energy closure remain unresolved. K-030 stays open; no surrogate or guard replacement is adopted.

The bounded repeatability collection is complete (521 saved-output checks pass; every within-backend fresh-process repeat is exactly equal and agrees with its consumed output, while all four cross-backend discrepancies persist; native accounting completes within the reviewed bound and the offline archive copy matches its checksumC-201): both backends reproduce their own outputs exactly, while prior cross-backend discrepancies persist. Review numerical convergence and a conservative stable energy closure next. The current model/guard and K-030 remain unchanged.

Bounded numerical refinement is complete and audited (2076 integrity checks pass on the complete bounded study; baseline reproduction, signed species outputs, spectral accounting, native completion and the local archive copy are verified, while electron-flux signs change across refinement levels and finest-level backend differences remainC-203), but the reference remains unconverged: heat-flux signs change across levels and finest-level backend differences persist. Isolate width-search basis from final basis before a reference closure or candidate acceptance decision. Preparation checks pass (40 focused synthetic checks pass in each mode after the input-path correction, covering signed channels, refinement identities, baseline drift, incomplete evidence and existing diagnostic output handlingC-202); earlier failed attempts remain recorded.

The separated-basis diagnostic is complete and audited (2139 integrity checks pass on the complete 54-pair basis grid and all 36 consumed-control comparisons reproduce the preceding study; electron flux changes sign at every state, steps reach 4.28 gB along the final basis and 4.11 gB along the search basis, and at the largest final basis the flux is a residual of order 1e-3 gBC-205). Both the width-search and final-solve basis change the flux, and they interact. At the largest final basis the flux is a residual of order 1e-3 gB; the width search often stops at its upper bound. Convergence is still not established.

The basis and width-range extension is complete and audited (3029 integrity checks pass on the complete 78-pair extension and all 36 control comparisons reproduce job 2687308; NBASIS_MAX 16 still moves electron flux by up to 0.48 gB per step, and widening the width search from 1.65 to 3.3 changes it from about 1e-3 gB to as much as 181 gBC-206). A larger final basis does not settle the flux, and widening the width search changes it by orders of magnitude; the standard settings act as a convention (K-032). The reference choice is back with the owner.