Influence of electromagnetic fields on the dielectronic recombination of Ne7+ ions - art. no. 032707

The influence of crossed electric and magnetic fields on dielectronic recom bination of Ne7+ ions has been measured at the Stockholm heavy-ion storage ring CRYRING. The electron energy range covered all dielectronic recombinat ion resonances attached to 2s --> 2p(1/2) and 2s --> 2p(3/2) Deltan=0 core excitations, Two sets of measurements at magnetic fields of 180 mT and 30 m T have been per-formed. For the measurement at 180 mT we applied 25 differe nt electric fields between 0 and 1400 V/cm. The resonance strength for diel ectronic recombination via high Rydberg states initially increases linearly with electric field and later levels out. At a magnetic field of 30 mT we applied 15 different electric fields ranging from 0 to 140 V/cm. Compared t o the measurement at 180 mT the initial slope of the rate enhancement was l arger by almost a factor of 2. The fraction of resonant strength not measur ed due to field ionization is estimated by a model calculation of dielectro nic recombination cross sections.