BOSZ Data Processing

BOSZ spectra are staged as local source data under data/atmospheres/. The STScI HLSP page labels the archive path as bosz2024, but its 2025 Sept. 24 update states that the models were recomputed and earlier 2024 files should be replaced.

Local layout¶

data/atmospheres/bosz/2025-recomputed/
  provenance/
  wavelength/
    bosz2024_wave_r10000.txt
  scripts/
  raw/
    r10000/
      m+0.00/
  processed/
    catalog.parquet
    catalog_fragments/
    validation/
    bosz_2025_recomputed.zarr/

Everything under data/atmospheres/ is gitignored. Raw gzip spectra and processed artifacts are local cache products, not package data.

Precision policy¶

The converter parses the two released resampled columns as float64 for validation, then stores both arrays as float32 in the processed Zarr artifact. The shared wavelength grid is stored as float64.

This mirrors the NewEra policy: dense spectra are the storage bottleneck, while the wavelength coordinate is small and should remain precise. Downstream interpolation or integration may cast spectra back to float64 for accumulation.

The converter preserves the released BOSZ resampled columns as flux and continuum arrays. Unit-normalization and surface-flux interpretation belong at the downstream physical interface, not in the raw cache converter.

Conversion¶

Install the optional data tooling and run a dry-run first:

uv run --extra data python scripts/convert_bosz_resampled.py --dry-run

Convert the staged bridge subset:

uv run --extra data python scripts/convert_bosz_resampled.py --overwrite

For large BOSZ expansion, convert in batches by resolution, metallicity, and composition. Give each batch a stable group name:

uv run --extra data python scripts/convert_bosz_resampled.py \
  --raw-dir data/atmospheres/bosz/2025-recomputed/raw/r10000/m-0.50 \
  --wavelength data/atmospheres/bosz/2025-recomputed/wavelength/bosz2024_wave_r10000.txt \
  --group-name r10000_mminus0_50_v2 \
  --delete-raw-after-validate

Raw files are deleted only after the batch readback validation succeeds.