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تسجيل مستخدم جديدTidal tails in the disintegrating open cluster NGC 752
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We utilize the robust membership determination algorithm, ML-MOC, on the precise astrometric and deep photometric data from Gaia Early Data Release 3 within a region of radius 5$^{circ}$ around the center of the intermediate-age galactic open cluster NGC 752 to identify its member stars. We report the discovery of the tidal tails of NGC 752, extending out to $sim$35 pc on either side of its denser central region and following the cluster orbit. From comparison with PARSEC stellar isochrones, we obtain the mass function of the cluster with a slope, $chi=-1.26pm0.07$. The high negative value of $chi$ is indicative of a disintegrating cluster undergoing mass-segregation. $chi$ is more negative in the intra-tidal regions as compared to the outskirts of NGC 752. We estimate a present day mass of the cluster, M$rm_{C}=297pm10$ M$_{odot}$. Through mass-loss due to stellar evolution and tidal interactions, we further estimate that NGC 752 has lost nearly 95.2-98.5 % of its initial mass, $rm M_{i}~=~0.64~-2~times~10^{4}~M_{odot}$.
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