bamfai/galaxy-chirality-catalog

DESI Legacy Galaxy Chirality Catalog

This dataset accompanies the current Paper IV manuscript, An Observed-Label Chirality-Dipole Null in 949,584 High-Confidence DESI Spirals and an 8.5-Million-Galaxy Catalog.

The primary high-confidence observed-label statistic is consistent with zero under fixed-occupancy label randomization (z=0.7053169638, one-sided empirical-rank p=0.2246775322). This is not a calibrated true-spin, physical-amplitude, or primordial-parity bound.

Authoritative release

Use apjs-release/v1.0.244/, pinned by data commit db11023306ab4eed1d7727670bd78e127b7af17a and provider-receipt commit e535b26247c892971963be6029435544cf29d19b.

Product	Rows	Bytes	SHA-256	Role
p4_catalog_primary_safe_v1.0.244.parquet	8,474,531	386,712,994	139b761fbeafb34306a0cec60967226c18dc84295285f8317ce3d3af3d28bdf3	Science-facing observed-label catalog
p4_catalog_raw_flip_quarantine_v1.0.244.parquet	249,066	16,665,663	fb98787dd4c5d1a7a0fdb64fcdacd1b02bc2080ab3716c0a803e0ccdfec03fbe	Unsafe raw/flip reconstruction quarantine; do not use for science weights
primary_label_shuffle_amps_10000.npy	10,000 draws	80,128	f6360f4bec22669097cee3e2fad8b176291d3ecbfbfbb9a9290d0bce3d5152c0	Retained primary fixed-occupancy null
pixel_permutation_amps_10000.npy	10,000 draws	80,128	62bb1c019231974c2a7ed5d5e43ceb77a5596e4675c82d7ff1c899e029a36492	Distinct robustness diagnostic

The folder also contains the schema, manifest, SHA-256 ledger, validation receipt, and executable primary-null reproducer. Catalog C is the only published science-facing release product. The historical Catalog A (raw) and Catalog B (Platt-calibrated) labels describe pipeline diagnostics, not released catalog tiers; no complete Catalog B payload or executable release contract is claimed. The older root catalog_production.parquet is retained for provenance and contains raw-pass columns that are not calibrated probabilities; it is not the authoritative ApJS science product.

Safe-catalog schema

Column	Type	Meaning
object_id	string	DR8 compound identifier, BRICKID_OBJID
ra_deg, dec_deg	float64	ICRS coordinates in degrees
class_eq	string	Equivariant hard observed label: CW, CCW, or NOT_SPIRAL
score_cw_eq, score_ccw_eq, score_ns_eq	float64	Uncalibrated equivariant ranking scores
score_eq_max	float64	Maximum equivariant ranking score; not calibrated confidence
is_spiral	bool	class_eq is CW or CCW
primary_hc	bool	Declared high-confidence spiral selection
raw_flip_qc_unsafe	bool	Row belongs to the separately quarantined raw/flip diagnostic set

Morphology companion and executable join

spiral_morphology_dr8.parquet is the existing public morphology companion for every one of the 3,201,160 released CW/CCW rows. It is 105,317,121 bytes with SHA-256 d49090fce3033c5905df359f63036fd831c4b6378c271b95afd8d86a91bd5620. Its BRICKID_OBJID keys are unique, non-null, and exactly cover the safe catalog's is_spiral == True object IDs.

The current DR8 class totals are 1,592,107 CW and 1,609,053 CCW, totaling 3,201,160 chirality-relevant spirals.

The companion exposes raw DR8 morphology fields only: BRICKID, OBJID, TYPE, FRACDEV, SHAPEDEV_R, SHAPEDEV_E1, SHAPEDEV_E2, SHAPEEXP_R, SHAPEEXP_E1, and SHAPEEXP_E2. It does not contain a precomputed axial ratio.

The versioned machine-readable join contract, schema, and validator are under apjs-release/v1.0.251-morphology-sidecar/.

import pandas as pd
from huggingface_hub import hf_hub_download

repo = "bamfai/galaxy-chirality-catalog"
safe = pd.read_parquet(hf_hub_download(
    repo,
    "apjs-release/v1.0.244/p4_catalog_primary_safe_v1.0.244.parquet",
    repo_type="dataset",
    revision="db11023306ab4eed1d7727670bd78e127b7af17a",
))
morph = pd.read_parquet(hf_hub_download(
    repo,
    "spiral_morphology_dr8.parquet",
    repo_type="dataset",
    revision="245ad7c5f1e58c627be1390dc3125cd1ce1e3dc9",
))
morph["object_id"] = morph["BRICKID"].astype(str) + "_" + morph["OBJID"].astype(str)

assert not morph["object_id"].duplicated().any()
spirals = safe.loc[safe["is_spiral"]].merge(
    morph, on="object_id", how="left", validate="one_to_one", indicator=True
)
assert len(spirals) == 3_201_160
assert spirals["_merge"].eq("both").all()

Metadata not released

This release does not provide a full-catalog redshift, imaging-leg, depth, seeing, or PSF table. Those fields must not be inferred from the stale root README, which previously advertised columns absent from the Parquet files. A 145,789-row DESI-selection artifact used elsewhere in the project is selection-specific and is not a full-catalog redshift companion. Depth/PSF brick joins and imaging-leg rules remain unresolved publication work.

Reproducibility and citation status

• Paper source and pipeline: https://github.com/Hubify-Projects/bigbounce/tree/main/pipelines/p2_chirality
• Current manuscript source: https://github.com/Hubify-Projects/bigbounce/blob/main/pipelines/p2_chirality/chirality_catalog_paper.tex
• Machine-readable release contract: apjs-release/v1.0.244/SCHEMA.json
• Direct immutable machine-readable manifest: https://huggingface.co/datasets/bamfai/galaxy-chirality-catalog/resolve/db11023306ab4eed1d7727670bd78e127b7af17a/apjs-release/v1.0.244/MANIFEST.json
• Provider receipt: apjs-release/v1.0.244/PROVIDER_RECEIPT.json

No arXiv identifier, Zenodo DOI, or immutable repository tag for the current Paper IV manuscript has been assigned. Cite the manuscript title, author, and the pinned data/provider commits above until those identifiers exist.

License

Catalog data are CC BY 4.0. Underlying DESI Legacy Imaging Surveys imagery remains subject to the survey's terms.