Charge transfer and ionization in collisions between multiply charged noble gas ions

Using the crossed-beams technique we have measured absolute total cross sections for charge transfer and ionization of fourfold charged ions of argon, krypton and xenon. In the centre-of-mass energy range from 10 to 60 keV total cross section values around 10-16 cm2 have been obtained. In addition, using near-threshold electron-impact ionization, the fraction of metastable ions was estimated to be of the order of 12%-29% for Ar to Xe, respectively. Based on the measured cross sections, expected particle losses in future storage rings, which are currently under discussion, have been calculated.