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تسجيل مستخدم جديدExploring the Mass Segregation Effect of X-ray Sources in Globular Clusters. II. The Case of Terzan 5
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Using archival {it Chandra} observations with a total effective exposure of 734 ks, we derive an updated catalog of point sources in the massive globular cluster Terzan 5. Our catalog covers an area of $58.1, rm arcmin^{2}$ ($Rleq 4.3 , rm arcmin$) with 489 X-ray sources, and more than $75%$ of these sources are first detected in this cluster. We find significant dips in the radial distribution profiles of X-ray sources in Terzan 5, with the projected distance and width of the distribution dips for bright ($L_{X} gtrsim 9.5times 10^{30} {rm erg ,s^{-1}}$) X-ray sources are larger than that of the faint ($L_{X} lesssim 9.5times 10^{30} {rm erg ,s^{-1}}$) sources. By fitting the radial distribution of the X-ray sources with ageneralized King model, we estimated an average mass of $1.48pm0.11,M_{odot}$ and $1.27pm0.13,M_{odot}$ for the bright and faint X-ray sources, respectively. These results are in agreement with that observed in 47 Tuc, which may suggest a universal mass segregation effect for X-ray sources in GCs. Compared with 47 Tuc, we show that the two-body relaxation timescale of Terzan 5 is much smaller, but its dynamical age is significantly younger than 47 Tuc. These features suggest that the evolution of Terzan 5 is not purely driven by two-body relaxation, and tidal stripping effect also plays an important role in accelerating the dynamical evolution of this cluster.
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