Rizwan Ahmad Qureshi2022-05-182022-05-185232https://drepo.sdl.edu.sa/handle/20.500.14154/742Energy transfer between 4p3d (¹D,³P, ³F, ³D), 4s5p ³P, 4s4d ³D and 4p² ³P state of Ca was investigated following a two-step selective excitation of specific atomic states using pulsed lasers. Transfer of population to nearby states was monitored as a function of Ar pressure through a systematic study of flourescence. The main channels of decay were identified and information on the rate constants for Ca-Ar collisions was obtained. The experimental results together with a computer model developed to simulate the experiment is presented.enThesis