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arXiv · 2605.22163

A Unified H i Rotation Curve Database for 129 Local Volume Dwarf and Irregular Galaxies

David C. Flynn
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Abstract

We present a unified H i rotation curve database for 129 dwarf and irregular galaxies drawn from four Local Volume surveys: the Local Volume H i Survey (LVHIS; 33 galaxies), VLA-ANGST (29), LITTLE THINGS (26), and WALLABY DR2 (41). The database provides standardised kinematic parameters, distance estimates, morphological classifications, and rotation curve data in machine-readable JSON, JSONL, and CSV formats with a documented 27-field schema, supporting retrieval-augmented generation (RAG) applications and cross-survey kinematic analysis. Quality tiers distinguish 26 galaxies with full multi-point tilted-ring rotation curves from 103 with single-ring or profile-width estimates. Three worked examples demonstrate corpus queries, including application of the {\omega} correction to DDO 154 (LITTLE THINGS). This work is presented as a data resource; no new dynamical model is proposed. The database and all computation scripts are available at Zenodo (https://doi.org/10.5281/zenodo.20320362).

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David C. Flynn. 2026-05-21. A Unified H i Rotation Curve Database for 129 Local Volume Dwarf and Irregular Galaxies. https://arxiv.org/abs/2605.22163

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