Energy loss straggling of protons in thick absorbers

摘要: The energy loss of charged particles transmitted through an absorber is subject to fluctuations due the statistical nature excitation and ionization processes involved. For initially monoenergetic beam incident on uniform thickness there will be distribution function associated with emergent particles. Consider first case where fractional in ∆E/E < 0.1 but ΔE very much greater than lost a single collision. Here for initial E x, after passing depends spectrum In does not vary appreciably collision alter much. this case, originally treated by Bohr(1), Gaussian. However, if we now consider thicker can no longer regarded as constant over whole change. This consideration has been taken into account Tschalar(2) who calculated straggling distributions protons absorbers which up 0.8.