The Mass Spectrometry society of Japan - The 68th Annual Conference on Mass Spectrometry, Japan
Japanese

Abstract

Table of contents

Timetable

Plenary Lectures

Society Featured Lecture

Oral Sessions (Day1, Day2, Day3)

Poster Presentations (Day3)

Workshops

Lunchtime Seminars (Day1, Day2, Day3)

Oral Sessions

Day 2, May 20（Thu.）　11:40-12:00　Room C (Zoom)

2C-O8-1140　　PDF

Ultra-Low Blank Noble Gas Analysis for Extraterrestrial Materials

(1Hokkaido Univ., 2Kyushu Univ.)
oKenichi Bajo1, Ryuji Okazaki2

Noble gas analysis for returned samples by Sample return missions have been investigated to understand formation/metamorphism age, cosmic-ray exposure age, and surface environment of parent bodies. Noble gas initial analysis for Hayabusa mission revealed space weathering process on the Itokawa surface. Returned sample from Hayabusa 2 mission also reveals surface property on the Ryugu, 1999 JU3. Noble gas analysis for returned samples requires high sensitivity and low blank measurement because of their limited materials. We demonstrate ultra-low blank analysis for Ca-Al-rich inclusion (CAI) from Allende meteorite using modified MM-5400 in Kyushu University. The blank level of this measurement was ~2 × 10-13 cm3STP (9 × 10-18 mol). The CAI preserved radiogenic 22Ne from 22Na because we observed clearly excess of 22Ne from the CAI. Sodium-22 would be produced by spallation with solar cosmic-ray and disk gas at the early solar system. The radioactive 22Na and stable 23Na were incorporated into the CAI melilite at the CAI formation.