astro-legacy-archive/archeops-released-maps

Archeops released numerical products

LAMBDA's Archeops release supplies nine numerical files: a CMB power spectrum, covariance matrix, window functions, and 353 GHz dust-polarization power spectra. Each configuration is one served file. The paired ASCII and FITS products remain distinct because their published numerical precision differs.

Use

python -m venv .venv && .venv/bin/pip install datasets huggingface_hub pyarrow

from datasets import load_dataset
rows = load_dataset("astro-legacy-archive/archeops-released-maps", "power_spectrum_arch_v2.fits", split="train[:3]")
print(rows.column_names, len(rows))

import json
from huggingface_hub import hf_hub_download
import pyarrow.parquet as pq
path = hf_hub_download("astro-legacy-archive/archeops-released-maps", "covar_arch_v2.fits.parquet", repo_type="dataset")
print(json.loads(pq.read_metadata(path).metadata[b"dense_matrix"])["array"]["shape"])

Structure

The five table configurations use statistical-product 1.4.0. The four covariance/window arrays use dense-matrix 1.0.0. FITS field identifiers and ASCII header labels are preserved verbatim. The headerless dust tables use Column 1 through Column 10, an ordinal expansion of LAMBDA's ordered ten-field description; no semantic names are invented.

The covariance arrays are 25 by 25. Window-function arrays are 1,001 by 25. CMB power spectra have 25 rows, and each dust cut has 14 rows.

Provenance and considerations

LAMBDA serves the product table covering all nine numerical files, the download table covering the six CMB files, and the detailed description. Source hashes, complete ASCII or FITS headers, ordering, identifiers, units, credit, and structured regeneration command are embedded in every Parquet file. Each footer names the unpublished astro-legacy-archive conversion-tools repository at commit 90d64c0b0c51b4e67c446b74453215dbe6f48c0a, run from its root as python tools/make_archeops_released_products.py --out data/archeops-released-maps --source SOURCE_DIR --provenance-commit 90d64c0b0c51b4e67c446b74453215dbe6f48c0a.

Use one source representation consistently: the ASCII CMB products are rounded relative to FITS. Dust fields are in microK_RJ^2; the CMB spectrum and covariance are in uK^2 and uK^4.

Licensing and citation

HEASARC states: “HEASARC materials are all available freely for your use.” This is a free-use statement, not a named formal licence. LAMBDA credits “M. Tristram and J.F. Macias-Perez - November 2004”. Cite Tristram et al., The CMB temperature power spectrum from an improved analysis of the Archeops data, Astronomy & Astrophysics 436, 785–797 (2005), DOI 10.1051/0004-6361:20042416, and the product-specific papers collected on LAMBDA's Archeops publications page. LAMBDA also asks users to acknowledge it as a HEASARC service at NASA Goddard; see its acknowledgement guidance.

Errata and requests

Report corrections or dataset requests in the dataset's Community tab.