We are grateful to JNOC, JAPEX, HNIRI, FRL, and FTRI for allowing us to publish the data obtained in this collaborative study. The laboratory assistance of H. Iwano and Y. Kajiwara (JAPEX Research Center) is greatly appreciated. This research was partly supported by the Grant-in-Aid from the Ministry of Education and Culture (07559004) and research grant from the Iwatani Naoji Memorial Foundation to RM.