Developments of characterization of the foam shell target for fast ignition realization experiment-I (FIREX-I)

Equipments and techniques have been developed for characterization of the foam shell target for the FIREX-I. An interference measurement technique is planned to use to measure the quantity of fuel in a foam shell. A preliminary experiment of the interference measurement technique was carried out. Experimental results indicate the refractive index of RF foam is near 1.08 and that of vacant RF foam containing liquid H2 is near 1.22. Calculations indicate the refractive index of vacant RF foam is 1.07 and that of RF foam containing H2 is 1.19. Some causes of these differences were discussed.