Photon emission under MeV carbon cluster impact for probing cluster–solid interactions

Abstract

First experimental results on the luminescence induced in thin molecular samples by the impact of single cluster ions Cn+ (n=2–10) at 1 MeV/atom have been reported. The cluster ions were produced and accelerated at the Erlangen tandem accelerator. The samples were a 1 μm CsI layer deposited onto a 2 μm aluminized polyester foil and a 100 nm POPOP layer prepared onto a 20 nm formvar film. The bombarding ions could traverse the samples but the cluster constituents did not remain in proximity in all cases. The luminescence was registrated by time-correlated single photon counting using either secondary electrons or transmitted clusters for starting the measurement. The relative photon yield obtained with clusters of various size increases linearly with the number of cluster constituents. The increase is less pronounced in case of the thin sample. This experimental result can be explained by the fact that the cluster ions leave the exit side of the sample as intact entities and that the photon emission is reduced in regions of high energy density.