Characterization of sub-micron sized clusters in a supersonic gas jet using Mie scattering

Jinno, Satoshi   ; Fukuda, Yuji; Sakaki, Hironao; Yogo, Akifumi; Kondo, Kiminori; Faenov, A. Ya.*; Skobelev, I. Yu.*; Pikuz, T.; Boldarev, A. S.*; Gasilov, V. A.*

High-energy ion generation has been achieved by using cluster-gas targets in the laser driven ion acceleration. In this experiment, a three-step conical nozzle, designed based on the Boldarev's model, was used to prepare large sized clusters. However, a characterization of the targets formed by this nozzle was not sufficient to further investigate the ion acceleration mechanism and optimize the acceleration condition. For this reason, in present work, the target diagnosis apparatus applying Mie scattering and interferometry has been developed. CO clusters are formed in the supersonic jet of the mixture gas of H and CO through the three-step conical nozzle. We have estimated the size distribution of CO cluster by measuring the angular distribution of scattering light from the clusters for laser irradiation. The density profile was obtained from the phase shift of the laser light acquired by the interferometer. These results were compared with the Boldarev's model.