Stripping of fast heavy low-charged ions in gaseous targets

Projectile-ionization (stripping) cross-sections and beam lifetimes have be en calculated for heavy low-charged ions of Pb, Bi and U colliding with H, He, Be, Li, F, N, Ar and Xe atoms in the E = 1-100 MeV/u energy range. Calc ulations have been performed for single-electron processes in the Born appr oximation using the LOSS computer code accounting for the atomic structure of the target. Results are compared with available experimental data, CTMC calculations and Z(2) +Z scaling where Z is the nuclear charge of the targe t atom. In the case of Pb-like ions (Pb0+, Bi1+...... U10+), the scaling la w for the stripping cross-sections on the projectile charge and the target nuclear charge is obtained. In the energy range considered, the calculated cross-sections are proportional to Z(1.4) due to the screening of the targe t nucleus by its electrons which differs markedly from the V-dependence, gi ven by the first-order perturbation theory. The role of multi-electron proc esses is briefly discussed. (C) 2001 Elsevier Science B.V. All rights reser ved.