Paper 1B

You are an external referee for MNRAS / Physical Review D / JCAP (target journal depends on paper).

Attached: Paper 1B v1B.0.97 — "Technical Verification Companion to the ECH Spin-Torsion Program: ΛCDM+ΔN_eff MCMC Proxy, NaMaster Pipeline Recovery, and a Birefringence Consistency Check with a Spectator-ALP Model"
Source: arxiv/paper1b_mcmc_companion.tex
PDF: PDF · 24 pp · v1B.0.95 · updated Jul 1, 2026 · md5 69b0983f

Read the FULL PDF end-to-end. Produce a referee report in MNRAS format with:

1. Recommendation: ACCEPT / MINOR REVISIONS / MAJOR REVISIONS / REJECT
2. BLOCKERS (must fix before publication) — list each with section/line + proposed fix
3. MAJORS (should fix) — same format
4. MINORS (polish) — same format
5. Strengths (>= 3 bullet points)
6. Specific scrutiny on:
   - 309,189 MCMC posterior samples across 2 converged dataset combinations (176,240 full-tension + 132,949 Planck+BAO+SN)
   - ΔNeff ≈ 0 result: +0.058±0.179 (Planck+BAO+SN, chain-recomputed EXT2)
   - NaMaster pseudo-C_ℓ pipeline 500 MC recovery at SNR=20.32σ
   - Spectator-ALP carved-out regime (f_a ~ M_Pl, m ~ H_0) — explicit parameter-restriction where Ω_φ ≪ Ω_crit holds

CALIBRATION (do not burn findings on these known classes):
- The current date is June 2026. arXiv identifiers of the form 25xx.xxxxx and 26xx.xxxxx are VALID, already-published preprints — do not flag them as "future-dated" or "nonexistent". Verify a citation against arXiv/ADS before claiming it does not exist.
- Correction notes, retraction notices, and "an earlier version stated X" disclosures in the text are DELIBERATE transparency policy. Flag them only if their content is wrong, never for existing.
- Companion-paper citations marked "posted concurrently on arXiv" are deliberate placeholders; real arXiv IDs are inserted during the coordinated submission sequence.
- Explicitly labeled conservatism allowances, scaling estimates, ansatz/heuristic status labels, and disclosed queued follow-up computations are deliberate scoping, not oversights — flag only if the label itself is inaccurate.
- PDF text extraction can mangle math (square roots, fractions, superscripts). Before flagging "garbled" or "wrong" math, consider extraction artifacts; flag only what is visibly wrong in the rendered PDF.

VERDICT STANDARD (apply the SAME high bar a first-pass Physical Review D / MNRAS referee would — this is one of the most rigorous journals in the world):
- Assign each finding's severity (BLOCKER / MAJOR / MINOR) by your own independent referee judgment. Do NOT default to any tier, and do NOT soften a finding because the rest of the paper is strong. Do not echo this prompt's context.
- A reporting choice that headlines the more favorable of two numbers, an unstated assumption, an uncontrolled systematic, or an internal inconsistency IS a real finding — classify it honestly (MINOR at minimum), not as mere "style" or "opinion".
- Truth-audit any claim that seems off by checking it against the published .tex / on-disk artifacts before flagging (this only filters out genuine extraction artifacts — it does not lower the bar on real defects).