Upper-limit determination of resonant trielectronic recombination cross-section for krypton using crystal channeling -: art. no. 022724

We used channeling through a thin crystal to get an estimate of the cross section of the resonant trielectronic capture by Kr34+ ions. K x-ray-K x-ray coincidence measurements were performed with a selection on the charge state and energy loss of transmitted ions. An upper limit of 1.9 x 10(-27) cm(2) at the resonance is obtained, and this: represents an improvement by two orders of magnitude with respect to previous ion-gas experiments. The possibility to reach the theoretical predictions experimentally is discussed.