Photometric and Kinematic Study of the Open Clusters SAI 44 and SAI 45

Abstract We carry out a detailed photometric and kinematic study of the poorly studied sparse open clusters SAI 44 45 using ground-based BVR c I data supplemented by archival from Gaia eDR3 Pan-STARRS. The stellar memberships are determined statistical method based on data, we found 204 members in while only 74 identified 45. average distances to calculated be 3670 ± 184 1668 47 pc. logarithmic age 8.82 0.10 9.07 yr for 45, respectively. color–magnitude diagram hosts an extended main-sequence turnoff (eMSTO). apparent spread is similar predicted basis cluster relation rotation models. This indicates that eMSTO evolution rather than star formation phenomenon conclude mainly caused different rates stars as SYCLIST synthetic population with was able reproduce observed eMSTO, red part were preferentially concentrated inner region, which again hints at rotations being reason extension upper MS. finding supports theory attributing origin stars. mass function slopes obtained −2.24 0.66 −2.58 3.20 rages 2.426–0.990 M ⊙ 2.167–1.202 exhibits signature segregation weak evidence possibly due tidal stripping. dynamical relaxation times these indicate both dynamically relaxed state. Using AD-diagram method, apex coordinates ( $69\buildrel{\circ}\over{.} 79\pm 0\buildrel{\circ}\over{.} 11$?> 69 .° 79 ± 0 11 , − $30\buildrel{\circ}\over{.} 82\pm 15$?> 30 82 15 ) (− $56\buildrel{\circ}\over{.} 22\pm 13$?> 56 22 13 62\pm 62 space velocity components units km s −1 (−15.14 3.90, −19.43 4.41, −20.85 4.57) (28.13 5.30, −9.78 3.13, −19.59 4.43),