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The problem is that the Gamma Knife radiosurgery can be inaccurate and when it is inaccurate, it can bear dangerous consequences, namely harming healthy brain tissue.  \section{Gamma Ray Knife}  Stereotactic radiosurgery delivers a single high dose of ionizing radiation to a small intracranial 3D brain tumor without (hopefully) delivering any significant fraction of the prescribed dose to the surrounding healthy  brain tissue. tissue surrounding the tumor.  The gamma knife delivers a single high dose of ionizing radiation emanating from 201 cobalt-60 unit sources through aheavy  helmet. Each irradiation is known as  a “shot,” "shot",  which resembles a circle. Multiple shots can be used if a single shot cannot individual shots do not  cover the target. Helmets have beam channel diameters of 4, 8, 14 & 18 mm. \section{Circle Packing}  In geometry, circle packing is the study of the arrangement of circles (of equal or varying sizes) on a given surface such that no overlapping occurs and so that all circles touch another. The associated packing density of an arrangement is the proportion of the surface covered by the circles. In two dimensional Euclidean space, the optimal lattice arrangement of identically-sized circles with the highest density is the hexagonal packing arrangement. The packing density of this arrangement is about 0.9069. Generalizations can also be made of higher dimensions – this is called "sphere packing", which usually deals only with identical spheres. We dealt only with circles for our first model for simplicity.