ATLAS100: Comprehensive Catalog of 1,729 Supernovae and Transients Within 100 Megaparsecs
Researchers have published ATLAS100, a catalog of 1,729 supernovae and related explosive transients observed within approximately 100 megaparsecs over 5.75 years by the ATLAS survey. The sample is volume-limited to galaxies with spectroscopic redshift z ≤ 0.025, achieves 83 percent host galaxy redshift completeness, and 87 percent spectroscopic classification completeness. The catalog provides a statistically robust, well-characterized dataset for studying supernova demographics, rates, and progenitor populations in the local universe.
The ATLAS100 catalog, compiled from observations spanning September 2017 to June 2023, presents 1,729 supernovae and other explosive optical transients detected by the Asteroid Terrestrial-impact Last Alert System (ATLAS) within roughly 100 megaparsecs. The sample is constructed by cross-matching transients against a comprehensive host galaxy list aggregated from all available redshift and distance catalogs, selecting events within a projected radius of 50 kiloparsecs of their hosts. Host galaxy redshift completeness stands at 83 percent, consistent with known completeness limits of local galaxy catalogs, while spectroscopic classification completeness reaches 87 percent within the volume. Many previously ambiguous transients were reclassified using joint light curve and spectroscopic analysis. The team also fitted light curve data to derive peak luminosities and characteristic timescales for all transients, and the full catalog along with processed ATLAS photometry is being publicly released. This dataset is expected to support studies of supernova rates, type demographics, and the relationship between transient properties and host galaxy environments in the nearby universe.
What's missing
The paper does not detail the derived volumetric supernova rates broken down by type, nor does it discuss how the 17 percent host galaxy redshift incompleteness may bias demographic conclusions for specific subtypes. Long-term implications for Hubble constant measurements or cosmological distance ladder calibration using this sample are not addressed.
What different sources said
- arXiv astro-phCenter
ATLAS100 -- I. A volume-limited sample of supernovae and related transients within 100 Mpc
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