Collective Effects Such As the Polarization or the Plasmon Excitation Momentum Exchange in a Collision between the Ion and a Free Electron in the Target Material.ħ. The possible phenomena contributing to the electronic stopping in the velocity region well below the light velocity are 9:ġ. The nuclear component of the stopping power can also be ignored 7. At low energies the total energy loss is usually described in terms of electronic stopping power 10. The total stopping power is then just the sum of the stopping powers due to electronic and nuclear interactions 8, 9. If an ion beam penetrates through matter it loses energy due to collisions with electrons (electronic stopping) and target nuclei (nuclear stopping) 7. Early investigations of the energy loss of charged particles traversing matter arrive at a general stopping power formula 6. It depends on the charge and velocity of the projectile and, of course, the target material 5, 6. The stopping power is defined as the mean energy loss per unit path length– dE/ dx. Heavy charged particles traversing matter lose energy primarily through the ionization and excitation of atoms 4. The Stopping power and energy dissipation of charged particles through matter has been a subject of great interest for 100 years 1, 2, 3 because of its wide areas of application, such as ion implantation, fundamental particle physics, nuclear physics, radiation damage, radiology 2, 3. The total stopping power is proportional to Z 2, Z/A, and I, increases rapidly at low energies, reaches a maximum and decreases gradually with increasing energy. Total stopping power was obtained by summing the electronic collisional and radioactive stopping power of the target materials, and then employing the continuous slowing down approximation (CSDA) to calculate the path length (Range). Fitting model was employed using Matlab for water.
All these calculations were done using different programs SRIM, STAR and Matlab, the results will be shown for Range Vs energy, and stopping power vs energy. This has been done for different target materials in biological human body substances such as water, bone, muscle and tissue and at different energies of the ions. In this work we studied interaction of Ions radiations and alpha particles with matter we calculated the stopping power (in MeV cm2/g) and Range from the theory of Bethe-Bloch formula as giving in the reference. Radiation is naturally present in our environment and artificially in hospitals, both types of radiation interact with human body.
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