The fundamentals of estimating essential stellar parameters of an open
cluster-NGC 2360 and globular clusters-NGC 5272 are presented extensively in
this work. Here, the evaluation of stellar parameters, by manually fitting the
appropriate isochrones on the color magnitude diagrams (CMDs), of the selected
star clusters is discussed comprehensively. Aperture photometry and PSF fitting
photometry are conducted on g, r, and i standard band filter images of Sloan
Digital Sky Survey (SDSS) using the aperture photometry tool (APT) to obtain
the respective CMDs. Further, to achieve the stellar parameters, isochrone
fitting is described in detail. This work on stellar parameters evaluation has
attained the following results: age of NGC 2360 is found to be 708 Myrs with
metallicity, [Fe/H], of -0.15, whereas NGC 5272 is having age of 11.56 Gyrs
with metallicity, [Fe/H], of -1.57. Additionally, the interstellar reddening,
E(B-V), and distance modulus, DM, for NGC 2360 are obtained as 0.12 and 11.65,
respectively. While, for NGC 5272, the interstellar reddening is attained as
E(B-V)=0.015, and the distance modulus is DM=15.1. The values of these stellar
parameters are found to be in close approximation with the results provided in
the literature based on the IRAF analysis technique. The distribution of radii,
masses, and temperatures are included along with the initial mass function
(IMF) for both the start clusters. Thus, this article would aid in providing
insight into the evaluation of stellar parameters by the astronomical
photometry analysis which would successively upsurge the understanding of our
universe. It should be noted that the cleaning of cluster population on the
CMDs from the foreground/background stars, clearing of spurious objects, error
estimations and the membership determination are not carried out in this work
and are considered as separate project for analysis.
