Unified Galaxy HI Rotation Curve Corpus (v7.0): SPARC + THINGS + LITTLE THINGS + WALLABY DR2

# Unified Galaxy HI Rotation Curve Corpus (v7.0)

**SPARC + THINGS + LITTLE THINGS + WALLABY DR2**

Flynn, D.C. (EPS Research) | ORCID: 0000-0002-2768-6650 | davidflynn@eps-research.com

---

Summary

Version update (v7.0): Updated corpus files, expanded documentation, and revised ingestion and figure‑generation scripts. Scientific scope unchanged.

A unified corpus of **8,963 spatially resolved HI rotation curve measurements across 423 galaxies** from four major surveys, plus kinematic metadata for 15 additional THINGS galaxies (438 total). Designed for both traditional numerical analysis and LLM retrieval-augmented generation (RAG) pipelines.

All radii in kpc, all velocities in km/s. Kinematic parameters verified against scanned primary tables. Two-tier quality system: Tier 1 (hand-curated, per-point uncertainties) and Tier 2 (automated WALLABY pipeline).

| Survey | Galaxies | Data Points | Tier | Reference |
|--------|----------|-------------|------|-----------|
| SPARC | 175 | 3,391 | 1 | Lelli et al. (2016), AJ 152, 157 |
| THINGS | 34 (19 w/data) | 2,110 | 1 | de Blok et al. (2008), AJ 136, 2648 |
| LITTLE THINGS | 26 | 1,716 | 1 | Oh et al. (2015), AJ 149, 180 |
| WALLABY DR2 | 203 | 1,746 | 2 | Deg et al. (2022); Murugeshan et al. (2024) |
| **Total** | **438** | **8,963** | | |

## Files

- **rotation_curve_corpus_v7.json** — Master JSON (~2.0 MB). Single structured document with all 438 galaxies, nested per-ring data, metadata, column definitions, and quality annotations. Authoritative source.
- **rotation_curve_corpus_v7_flat.csv** — Catalog table (438 rows, 29 columns). One row per galaxy with summary statistics for filtering and sample selection.
- **rotation_curve_corpus_v7_by_galaxy.zip** — Per-galaxy JSON archive (438 files in SPARC/THINGS/LITTLE_THINGS/WALLABY subdirectories). Each file is self-contained with full corpus metadata. Optimised for LLM/RAG ingestion.
- **corpus_description_sheet_v7.docx** — Full corpus documentation.
- **READMEv7.md** — This file (extended version).
- **wallaby_ingest.py** — WALLABY DR2 ingestion script (supplementary).
- **make_figures_v7.py** — Figure generation script for the companion A&C paper (supplementary).

## Related Publication

Flynn, D.C. & Cannaliato, J. (2025). "A new empirical fit to galaxy rotation curves." *Frontiers in Astronomy and Space Sciences*, 12. DOI: [10.3389/fspas.2025.1680387](https://doi.org/10.3389/fspas.2025.1680387)

## Citation

> Flynn, D.C. (2026). *Unified Galaxy HI Rotation Curve Corpus (v7.0): SPARC + THINGS + LITTLE THINGS + WALLABY DR2.* Zenodo. DOI: 10.5281/zenodo.19563417

Please also cite the relevant underlying survey papers (see READMEv7.md Section 10).

## License

CC BY 4.0