HSLA Classifications

HSLA Classification Tiers

An important aspect of the HSLA project is the automated classification of all targets in the COS/STIS archive. Based on information from SIMBAD, NED, and the Phase II proposal, HSLA’s target-classification scheme is structured as a three-tiered hierarchy. For example, PKS 0405-123 is assigned a Tier 1 classification of Galaxy, Tier 2 of Active Galaxy, and Tier 3 of Seyfert Galaxy, while AzV 388 is classified as Star, Early-type star, and O Star. For details, please see the HSLA ISR (Debes et al. 2025).

Tiers and the Full Classification Scheme

If you're looking for a machine-readable format, you can use the full HSLA classifcation schema as a JSON file. Otherwise, classifications are sorted below into three tables, each table containing a Tier 1 schema. Tier 2 values occupy the left column of the table; corresponding Tier 3 values are in the right column and are color-coded to match their parent in Tier 2.