ALH77250隕鉄中のMn-53/Mn-55同位体比の精密測定 Precise Determination of the Mn-53/Mn-55 Isotopic Ratio in the ALH77250 Iron Meteorite
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The natural radiogenic nuclide ^<53>Mn is found in iron meteorites. In order to determine the half life of ^<53>Mn, the ^<53>Mn/^<55>Mn isotopic ratios in the ALH77250, which has high ^<53>Mn concentration, were measured precisely by the thermal ionization mass spectrometer. The average of the isotopic ratios, when the measured ion currents of ^<55>Mn were greater than 1×10^<-12> A and the interference of ^<53>Cr to ^<53>Mn was less than 10%, was (5.977±0.032)×10^<-5> (2σ_m). With combination of the X-ray measurements of ^<53>Mn, a new precise half life will be determined.
- Bulletin of the National Science Museum Ser. E Physical Sciences & Engineering
Bulletin of the National Science Museum Ser. E Physical Sciences & Engineering 25, 7-14, 2002
National Science Museum