Year: 2025
Type: article
Abstract: ABSTRACT We present the first study of the X-ray sources in one of the most metal-rich globular clusters in the Galaxy, NGC 6528. Using relatively deep (66 ks) archival imaging from the Chandra X-ray Observatory, we identify 18 sources within the half-light radius of the cluster, all in the range $L_X \sim 10^{31}$–$10^{32}$ erg s$^{-1}$ (0.5–7 keV). By combining these data with photometry from the Hubble Space Telescope and other sources, we classify the X-ray sources as a likely mix of cataclysmic variables and active binaries, though one or more of the brighter objects could be a quiescent low-mass X-ray binary. For this cluster, it appears that the X-ray binary-enhancing effects of high metallicity are outweighed by the cluster’s advanced dynamical evolution, leading to a relatively modest X-ray source population.
Authors: Bernard Leal, Kwangmin Oh, Jay Strader, Kristen C Dage, Stephen E Zepf, S Kim, C Y Hui
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Award: G1272287757
OpenAlex ID: W4413340175