ATLAS100: Comprehensive Catalog of 1,729 Supernovae and Transients Within 100 Megaparsecs
Astronomers have compiled ATLAS100, a volume-limited catalog of 1,729 supernovae and other explosive optical transients observed within approximately 100 megaparsecs (326 million light-years) over 5.75 years. The sample achieves 83% host galaxy redshift completeness and 87% spectroscopic classification completeness, with researchers reclassifying ambiguous transients using light curve and spectroscopic data. This comprehensive local transient catalog provides a foundation for understanding supernova demographics and rates in the nearby universe.
The ATLAS100 catalog represents a systematic compilation of transient events detected by the ATLAS survey from September 2017 through June 2023, focusing on nearby galaxies with spectroscopic redshifts of z ≤ 0.025. The researchers constructed a host galaxy list by aggregating multiple redshift and distance catalogs, then carefully selected all transients within a 50 kiloparsec projected radius of identified hosts. The resulting sample includes 1,729 supernovae and related explosive transients with high completeness metrics: 83% for host galaxy redshift determination and 87% for spectroscopic classification. The team performed light curve fitting to derive peak luminosity and characteristic timescales for each transient, and released the full catalog alongside cleaned ATLAS photometry data. This volume-limited approach enables robust statistical analysis of transient demographics and rates in the local universe.
What's missing
The study does not discuss potential implications for cosmological distance measurements, supernova standardization for cosmology, or how this sample compares to rates predicted by stellar evolution models. The paper's own limitations regarding the 17% incompleteness in host galaxy redshifts and potential selection effects from the ATLAS survey's detection capabilities are not detailed in the abstract.
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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