Round 2 verification audit for C046

Model: gpt-5

Claim: Fig. (discrete_eigenvalue): the second dominant eigenvalue lambda_max of S(pi/4,gamma,theta) as a function of (gamma,theta), minimized at theta^opt ~= 0.72 pi, gamma^opt ~= 0.22 pi.

Source alignment: source/supp_content.tex:29-34 (Fig. discrete_eigenvalue)

Prior official verdict: partial with failure_reason None.

Executable evidence: run.py. Sandbox rerun logs: run.log.

Independent audit: I scanned the copied script for imports/shared helper dependencies and reran it through the sandbox. The code is self-contained in this attempt directory and targets the claim strategy: Recompute lambda_max over the (gamma,theta) grid and compare the heatmap and its minimum to the figure.. I checked the relevant family model rather than relying only on exit status; the rerun is treated as one reproducibility input.

Decision: Round 2 verdict is partial with failure_reason None and limitations ['visual_match_only', 'paper_text_only_reimplementation']. Notes: Reproduced lambda_max heatmap of S(pi/4,gamma,theta) (self-contained model) over (theta in [0,pi], gamma in [0,pi/2]). Grid minimum lambda_max=0.87697 at theta=0.717 pi, gamma=0.221 pi vs paper theta^opt~0.72 pi, gamma^opt~0.22 pi; rate -1/log(lambda_max)=7.617 vs paper 1/7.62. Heatmap structure and RdBu color scale match. Theory-reproducible plot; Tier-A visual match only -> caps at partial.