@article{oai:nipr.repo.nii.ac.jp:00000969,
 author = {Nagao, Keisuke and Takaoka, Nobuo},
 journal = {Memoirs of National Institute of Polar Research. Special issue},
 month = {Mar},
 note = {P(論文), Concentrations and isotopic ratios of five stable rare gases were determined in six antarctic meteorites. Yamato-74191 chondrite (L3) contains large amounts of trapped heavy rare gases. Allan Hills No. 8 and Mt. Baldr No. 1 chondrites revealed short ages for cosmic-ray exposure, and are comprised in a cluster around 4 m.y. in a histogram of exposure ages for H-chondrites. This suggests a common parent body to these two chondrites. Yamato-74013 and -74097 diogenites are in close resemblance in amounts and isotopic ratios of cosmogenic He, Ne and Ar, and thus in their cosmic-ray exposure ages. Furthermore, their exposure ages resemble Yamato-692 diogenite but differ from other diogenites known to date. This strongly suggests a parent body common to these Yamato diogenites but not to the other ones. The U/Th-He ages are found to be shorter than the K-Ar ages. This is attributed to diffusive partial loss of He. Such loss was also observed for cosmogenic ^3(He). The K-Ar ages for Allan Hills No. 8 and No. 1,Mt. Baldr No. 1 and Yamato-74191 in order of antiquity are 4.5±0.2,4.4±0.2,4.1±0.2 and 3.4±0.2 b.y., respectively. ^<80>(Kr) and ^<82>(Kr) anomalies resulting from epithermal neutron capture by Br have been found in Yamato-74191. Allan Hills No. 1 contains cosmogenic Kr the isotopic composition of which is : ^<78>(Kr)/^<80>(Kr)/^<82>(Kr)/^<83>(Kr)/^<84>(Kr)/^<86>(Kr)=0.16±0.02/0.59±0.06/0.85±0.12/=1/0.47±0.28/=0. All chondrites investigated revealed enrichment in ^<129>(Xe). Among others excess ^<129>(Xe) in Yamato-74191 amounts to 3.02×(10)^<-9>(cm)^3 STP/g. An isotopic composition of trapped Xe in Allan Hills No. 8 which is depleted in Xe was identical with that of Xe-rich chondrites such as AVCC-Xe. Relation between trapped heavy rare gases and petrologic type is discussed.},
 pages = {207--222},
 title = {Rare Gas Studies of Antarctic Meteorites},
 volume = {12},
 year = {1979}
}