Collinder 261 Chandra X-Ray Point Source Catalog for an Ancient Open Cluster

107 X-ray sources were detected within the half-mass radius of the 7-billion-year-old open cluster Collinder 261 using the Chandra X-Ray Observatory. The observation, conducted on 2009 November 9 with a 53.8 ks exposure, aimed to uncover close interacting binaries and reached a limiting luminosity of ~4 x 10^29 erg s^-1. The data, provided by NASA, includes a mix of active binaries, candidate cataclysmic variables, and straggler stars.

Use Cases

• Study the correlation between stellar age and X-ray luminosity based on the cluster's 7 Gyr age and measured X-ray emissivity.
• Identify and classify binary star systems based on detected X-ray point sources and their estimated association with the cluster.
• Compare stellar population dynamics with other clusters like NGC 6791 based on the estimated cluster mass of 6500 solar masses.
• Analyze the impact of stellar density on binary destruction using X-ray emissivity trends mentioned for globular clusters and the local neighborhood.

Strengths

• Observation details are precisely documented, including the 53.8 ks exposure time, specific Chandra ACIS chips used, and the cluster's J2000.0 coordinates.
• The study provides specific astrophysical estimates, including ~26 cluster-associated sources above a luminosity threshold and an approximate cluster mass of 6500 solar masses.
• Source detection was performed across multiple energy bands (soft, hard, broad), suggesting a multi-faceted analysis.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment for certain analyses.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Data gathered from a Chandra X-Ray Observatory observation (ObsID 11308) using the Advanced CCD Imaging Spectrometer (ACIS).

Time Range

Observation date: 2009 November 9.

Freshness

Last updated 2026-03-13 17:38:39.431570; freshness should be verified.

Geography

Astronomical observation centered on the open cluster Collinder 261 (J2000.0 RA = 12h 38m 06.0s, Dec = -68° 22' 01").