抄録
We experimentally demonstrate the conditions where rare-gas cluster ion dissociates depending on the elastic response at the collision. Cluster ion consisting of thousands of argon atoms collide with the five kinds of metals at an incident energy per atom of less than 10 eV. The prominent ions in the mass spectra detected are dissociated ions such as dimer (Ar_2^+) or trimer ions (Ar_3^+). The branching ratio of the ion yield Ar_2^+/ΣAr_n^+(n ≥ 2), representing the dissociation rate, is significantly different by the metals. As a result, we found the dissociation rate of cluster ion is linearly increased with the impulsive stress acting on the contact area between the cluster ion and the metal surface. In addition, we discussed the possibility the result is applied to a new evaluation method of material strength.
