Stopping of slow projectiles in electron gas

New analytical formulas for the electronic stopping power and the energy loss straggling of low velocity extended charge projectiles in the degenerate electron gas are calculated within the dielectric function method. The stopping and straggling effective charges Z(eff) of a projectile were analysed. They ale found to differ one from the other and to depend on the electron gas density r(s), on the projectile atomic number Z(i) and on the projectile degree of ionization zeta. For small Z(i), due to antiscreening Z(eff) > 1.