: In this thesis we present a new calculation of the cascade of K ? p and K ? d atoms by the Monte Carlo method. Energy dependence of the collisional cascade processes is taken into account. The x-ray yields due to the radiative transition during the cascade are calculated as a function of density.We compare our results with the previous calculations by others and by KEK and DEAR experimental data for K ? p atoms. It shows that two processes, nuclear absorption and Stark mixing, have an important role in atomic cascades at high-density targets. ? 2 p =0.105±0.002 meV is approximately suggested for the 2 p strong interaction width of K ? p atoms by fitting our results with existing experimental data. In order to obtain the optimum density for measurement of the 1s strong interaction shift and width, we have investigated the stopping power of kaons in the targets together with the x-ray yields of kaonic hydrogen and deuterium. We have predicted the optimum range of the target density ? = 0.03–0.06 of liquid hydrogen density ( LHD ) for K ? p atoms and ? =0.06–0.2 of LHD for K ? d atoms in a forthcoming SIDDHARTA experiment. We have also investigated the kinetic energy distribution of K ? p atoms and the role of Coulomb transition on x-ray yields. Finally, the Doppler broadening contribution on the measured width of x-ray spectra are determined. In order to study the strong interaction in low energies, our results for x-ray yields from K ? p and K ? p atoms can be compared with the forthcoming SIDDHARTA collaboration results. In the second part of this thesis we have used the Key Word: Exotic atoms, kaonic atoms, nuclear absorption, atomic cascade dynamics, x-ray yields, Monte-Carlo method, cross sections.