An evaporation model for H2-clusters interacting with electrons and ions in a plasma

The evaporation rate of fast hydrogen clusters interacting with plasma particles is evaluated and compared with pellet penetration. It is shown that, because of their small size, only a small fraction of plasma particle energy is dissipated inside the clusters so that the evaporation rate is much less when the cluster size decreases below 105 atoms per cluster. These results are fairly consistent with the available experimental data.