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تسجيل مستخدم جديدA Gaia based photometric and kinematic analysis of the old open cluster King 11
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This paper presents an investigation of an old age open cluster King 11 using Gaias Early Data Release 3 (EDR3) data. Considering the stars with membership probability ($P_{mu}$) $> 90%$, we identified 676 most probable cluster members within the clusters limiting radius. The mean proper motion (PM) for King 11 is determined as: $mu_{x}=-3.391pm0.006$ and $mu_{y}=-0.660pm0.004$ mas yr$^{-1}$. The blue straggler stars (BSS) of King 11 show a centrally concentrated radial distribution. The values of limiting radius, age, and distance are determined as 18.51 arcmin, 3.63$pm$0.42 Gyr and $3.33pm0.15$ kpc, respectively. The clusters apex coordinates ($A=267.84^{circ} pm 1.01^{circ}$, $D=-27.48^{circ} pm 1.03^{circ}$) are determined using the apex diagram (AD) method and verified using the ($mu_U$,$mu_T$) diagram. We also obtained the orbit that the cluster follows in the Galaxy and estimated its tentative birthplace in the disk. The resulting spatial velocity of King 11 is 60.2 $pm$ 2.16 km s$^{-1}$. A significant oscillation along the $Z$-coordinate up to 0.556$pm$0.022~kpc is determined.
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