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arXiv · 2608.14101

A Reproducible Two-Boundary Kinematic Correction for Baryonic Rotation-Curve Reconstruction in an 84-Galaxy SPARC Benchmark

David C. Flynn
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Abstract

We present a reproducible computational validation and failure analysis of the empirical omega kinematic correction introduced by Flynn and Cannaliato (2025). The algorithm is deliberately minimal: one coefficient per galaxy is calculated from the innermost and outermost measured rotation-curve points and applied to the full observed radial profile before comparison with a baryonic reconstruction assembled from SPARC gas, disk, and bulge components. We preserve the predecessor's frozen 84-galaxy benchmark and publish its exact membership so that the transformation, not sample re-selection, is the object of validation. Without fitting the transformation to the baryonic residual, the primary maximum-disk reconstruction reduces the mean observed-baryonic discrepancy from 51.82 to 30.15 km/s across the frozen 84-galaxy benchmark. Bounded mass-to-light-ratio optimization further reduces the descriptive sensitivity-fit value to 25.45 km/s, while the simple Keplerian reference has a mean RMSE of 74.20 km/s in our earlier analysis [15]. Recalculation from the 84 per-galaxy records shows a resolved mass-to-light optimization benefit (delta RMSE > 0.05 km/s) in 53 galaxies and no resolved change in 31. Six galaxies do not beat the Keplerian reference; all six occur at Upsilon_max <= 0.111, whereas their omega values are not concentrated at the high end of the sample. We specify the complete deterministic workflow, native units, endpoint invariants, uncertainty propagation, and formula-level regression checks required to prevent grouping and sign errors. The complete 84-galaxy panel set, population-level error distributions, and failure diagnostics are retained as inspectable outputs. The result is a reproducible astronomical data-transformation benchmark rather than a proposed force law or replacement for dark matter or modified gravity.

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David C. Flynn. 2026-08-14. A Reproducible Two-Boundary Kinematic Correction for Baryonic Rotation-Curve Reconstruction in an 84-Galaxy SPARC Benchmark. https://arxiv.org/abs/2608.14101

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