Particle identification using dE/dx technique

The author has calculated the dE/dx particle identification prediction for two cases, one assuming that the central drift chamber has 60 samples 1 cm long operating at 1 atm gas pressure, and the other assuming a special dedicated dE/dx module with only 20 samples 1 cm long and a dedicated dE/dx gas. The attempt was to compare standard gases with helium based gases. To calculate this problem one needs to determine two quantities. First, the most probable energy loss (as a function of particle velocity, gas and the detector parameters), and second, the energy loss fluctuations as a function of similar parameters. The knowledge of these two quantities allows one to calculate the two particle separation in terms of a number of sigmas as a function of momentum