Bethe’s stopping number

Bethe's stopping number is a concept in physics that describes how charged particles lose energy as they pass through matter. Developed by physicist Hans Bethe, the formula for stopping power, -dE/dx, is a product of a kinematic factor and a stopping number.1

The kinematic factor depends on the particle's charge and mass, the density of atoms in the medium, and the particle's velocity. The stopping number, B, is influenced by the atomic number of the absorbing material and a term involving the particle's velocity and a mean excitation potential of the atom. Bethe's work, which earned him the Nobel Prize in Physics in 1967, was crucial in understanding atomic processes and energy production in stars.12