We present a detailed analysis of the structural parameters of the globular cluster M15 using g- and i-band photometric data from Pan-STARRS1 DR2. The central coordinates (XC, YC), ellipticity (), and position angle (PA) are derived via two independent methods: ellipse fitting of the two-dimensional stellar number isodensity distribution and Markov Chain Monte Carlo (MCMC) sampling. Our analysis of 38 stellar density intervals reveals a cluster center offset by only 4″.1 ± 9.″6 from the commonly accepted literature value, a good agreement on the order of our map resolution. We find a radial variation in the ellipticity, with a mean value of = 0.09 ± 0.02 for the inner region () and = 0.04 ± 0.02 for the outer region (), where the errors correspond to 1σ. The MCMC analysis of 75 datasets yields a mean = 0.022 ± 0.005 for the entire cluster. The PA remains constant with increasing distance from the cluster center, PA = 44.°4 ± 16.°2, and the MCMC method provides a consistent value of PA = 46.°6 ± 7.°1. Our results are in agreement with some recent studies but challenge others, suggesting that a single  value may be insufficient to fully characterize the overall oblateness of M15 due to incompleteness and crowding effects in its core.

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