Range Straggling of Charged Particles in Be, C, Al, Cu, Pb, and Air

The straggling of the range of charged particles due to fluctuations of the ionization loss has been evaluated for six substances (Be, C, Al, Cu, Pb, and air). The calculations extend up to Tμc²~100, where T is the kinetic energy and μ is the mass of the incident particle. At high energies (Tμc²5), the integral giving the range straggling becomes somewhat dependent on the ratio μm, where m is the electron mass. Two separate calculations have therefore been carried out, which apply to protons and μ mesons, respectively. The results for protons can also be used for π and K mesons in the energy range of interest (Tμc²5).