# SPARC corpus preparation report

**Status:** DATA PREPARED — CHAMBERS NOT RUN

## Source integrity

- Catalogue galaxies: 175
- Combined mass-model rows: 3391
- Individual ZIP members: 175
- ZIP-to-combined exact matches: 175

## Derived corpus

- Valid radial rows: 3389
- Excluded radial rows: 2
- Galaxies with at least one negative `Vgas` value: 48
- Negative-`Vgas` radial rows retained with signed-square treatment: 361
- Rows excluded because signed baryonic velocity squared was non-positive: 2

## Frozen baryonic calculation

```text
g_obs = (Vobs^2 / R) * 1e6 / kpc_m

g_bar = [Vgas*abs(Vgas) + 0.5*Vdisk^2 + 0.7*Vbul^2]
        / R * 1e6 / kpc_m
```

`Vgas*abs(Vgas)` preserves the direction encoded by negative SPARC gas
contributions. The stellar mass-to-light ratios are fixed, not fitted.

## Sample branches

- PRIMARY (`Q <= 2`, valid points >= 10): 121
- INCLINATION_SENSITIVITY (PRIMARY and inclination >= 30 deg): 115
- RESOLUTION_SENSITIVITY (`Q <= 2`, valid points >= 16): 75
- STRICT_SENSITIVITY (resolution branch and inclination >= 30 deg): 74
- BROAD_Q12 (`Q <= 2`, valid points >= 3): 163
- Q3_SENSITIVITY (`Q = 3`, valid points >= 3): 12

## Chamber boundary

This preparation generated chamber input ladders from retained
`log10(g_bar)` values at actual measured radii. It performed no interpolation,
no extrapolation, and no chamber execution.

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## v0.3 project interpretation

This document belongs to the external transfer experiment. Numerical, technical, protocol, or provenance content above is preserved. The transfer result tests one static global architecture: it does not negate the galaxy-specific structural information carried by the curves. Complete curves retain identity, and ρ is the leading channel for local or regime-conditioned follow-up.

