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

First experimental results on the luminescence induced in thin molecular sa mples by the impact of single cluster ions C-n(+) (n = 2-10) at 1 MeV/atom have been reported. The cluster ions were produced and accelerated at the E rlangen tandem accelerator. The samples were a 1 mu m CsI layer deposited o nto a 2 mu m aluminized polyester foil and a 100 nn POPOP layer prepared on to 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 lum inescence was registrated by time-correlated single photon counting using e ither secondary electrons or transmitted clusters for starting the measurem ent. The relative photon yield obtained with clusters of various size incre ases linearly with the number of cluster constituents. The increase is less pronounced in case of the thin sample. This experimental result can be exp lained 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 hi gh energy density. (C) 1998 Published by Elsevier Science B.V. All rights r eserved.