Sign in to view source links and access this dataset
Description
A catalog of 100,563 unresolved, UV-excess quasar candidates from the Sloan Digital Sky Survey Data Release One, covering 2099 square degrees. The National Aeronautics and Space Administration's HEASARC created this table in August 2005 based on published astronomical data. Existing spectra of 22,737 sources indicate a 97.6% quasar efficiency, with authors estimating 95.0% of the catalog objects are quasars.
Use Cases
Train and validate quasar classification models based on four-dimensional color distributions.
Estimate photometric redshifts for quasars based on the provided supplemental data.
Cross-match astronomical sources with radio (FIRST/VLA), X-ray (ROSAT), and optical (USNO-B) catalogs.
Study the efficiency and completeness of selection algorithms for broadband quasar surveys.
Strengths
High classification efficiency: 97.6% of spectroscopically confirmed sources are quasars.
Large sample size: 100,563 candidate objects.
High estimated purity: authors estimate 95.0% of the catalog objects are quasars.
Supplemental data includes photometric redshifts and cross-matches to other major catalogs.
Limitations
Column-level documentation is absent; field semantics must be inferred after download.
Data is based on SDSS Data Release One; newer data releases may supersede it.
Row count is unknown, which may limit suitability assessment.
Provenance
Source
Sloan Digital Sky Survey (SDSS) Data Release One, processed by NASA HEASARC.
Collection Method
Nonparametric Bayesian classification applied to training sets of stars and spectroscopically confirmed quasars.
Time Range
Based on SDSS Data Release One imaging data.
Freshness
Last updated 2026-03-13 17:41:26.714913; freshness should be verified.
Geography
Covers 2099 square degrees of sky surveyed by SDSS.
License is listed as 'other-license-specified'; terms should be reviewed before use. File formats include BIN and HTML.