SACY Catalog: Young Stars and Associations from Southern Hemisphere X-ray Sources

The SACY (Search for Associations Containing Young Stars) Catalog contains results from a high-resolution optical spectroscopic survey targeting nearby young associations. It includes data for 1626 stars in the primary sample, derived from observations of 1511 targets selected from 1953 late-type optical counterparts to ROSAT X-ray sources. The catalog was created by the HEASARC in March 2007 based on observations conducted primarily at ESO's La Silla observatory between 1999 and 2002.

Use Cases

• Identifying young stellar associations based on spectroscopic youth indicators like the LiI line strength.
• Analyzing the correlation between X-ray emission from ROSAT sources and stellar youth in the Southern Hemisphere.
• Studying stellar properties and multiplicity using corrected photometric data from Hipparcos, Tycho, and other sources.

Strengths

• Targeted selection of 1953 late-type, potentially young stars from a larger pool of 9574 X-ray sources.
• High-resolution spectra obtained for 1511 primary targets, with data supplemented by 115 stars from literature.
• Observations performed with high-resolution spectrographs (FEROS, coude) at major observatories (ESO/La Silla, OPD/Brazil).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data may reflect geographic bias inherent to its Southern Hemisphere focus.

Provenance

Source

National Aeronautics and Space Administration (NASA), HEASARC.

Collection Method

High-resolution optical spectroscopic survey of optical counterparts to ROSAT All-Sky Survey X-ray sources.

Time Range

Observations conducted primarily between January 1999 and September 2002.

Freshness

Last updated 2026-03-13 17:36:44.844723; freshness should be verified.

Geography

Southern Hemisphere, with northern boundary limits defined in the reference paper.