# LIB2-281 — Superseded cylinder formula for the reactor angle

- class: RETIRED · review_state: PUBLISHED · house_tier: not yet assigned
- labels as printed: math_status None · attachment None · scorecard tier word none (PDF p.None)
- basis: {"pdf_sha256_prefix": "b64ddcd9e16a6dcd", "release": "Rev33.1_S369"}

## Statement

The archived reactor-angle prompt proposed an electromagnetic-power arctangent from the Peirce cylinder as its mixing-angle target.

## Caution

The current reactor expression retains an unforced readout premise; replacing the older target does not prove a universal cylinder-model exclusion.

## Primary source

Paper 5, §2, Retained reactor-angle expression, PDF p.83: "sin2 θ13 = sin4 (π/8)"

## Machine

- url: /library-v2/LIB2-281/
- content_sha256: 4ab40033117bf90a9a353bacf693f8d8e3ab15659046f189df8e824b671da059
- candidate_ids: C2-006 C2-060

## Freshness

- BUILD_STAMP S371a · 2026-09-26T22:53Z · master 01d1a5873ede42f5 · cut 9dcc6ce9a8ee3e02
- Declared volatile fields (R36): BUILD_STAMP