An Investigation of Poorly Studied Open Cluster NGC 1746 Using Multicolor Photometric and Gaia DR2 Astrometric Data

Devendra Bisht (USTC China), Qingfeng Zhu (USTC China), Geeta Rangwal (DSB Campus, Kumaun University, Nainital, India), Alok Durgapal (DSB Campus, Kumaun University, Nainital, India), R. K. S. Yadav (ARIES, Nainital, India)

We have used the multi-colour photometric data are collected from Gaia DR2, APASS, UKIDSS, Pan-STARRS1, 2MASS, and WISE surveys for the comprehensive analysis of open cluster NGC 1758. The extinction law is found to be normal using different colour-colour diagrams. Cluster members are identified by applying distances based on the Gaia DR2 parallaxes and the point vector diagram of the Gaia DR2 proper motions. We calculated the main fundamental parameters (Age, distance, reddening, metallicity etc.) for this cluster. Galactic orbits and several orbital parameters are determined using Galactic potential models. Our study indicates that NGC 1746 has circular orbits (eccentricity~0). In addition to this, we also have studied the luminosity function, mass function and dynamical state of the target cluster for the first time. Mass function slope for the entire region of NGC 1746 is found to be comparable with the Salpeter’s value. A comparison of dynamical age with cluster’s age indicates that this object is dynamically
relaxed cluster. Main/important results will be explained later on at the time of talk.