演題概要

オーラルセッション

第3日 5月16日(金) 9:00~9:40 C会場(星雲2)

プレソーラー粒子の研究における最近の進展について

(ワシントン大学)
o甘利幸子

Presolar grains are defined as grains that had formed in stellar outflow or stellar ejecta and were incorporated into meteorites, remaining intact throughout the journey to the earth. Studies of these grains have yielded a wealth of information about nucleosynthesis in stars, mixing in stellar ejecta, and temporal variations of isotopes and elements in the Galaxy. Major progress in this field has been achieved when state-of-the-art instruments have been built and applied for analysis. A NanoSIMS, with high special resolution and high sensitivity, made it possible to find presolar silicate grains with sub-micron in size. Grains can be extracted from a substrate using Focused-Ion-Beam techniques and detailed isotopic and structural studies can be carried out. Two types of new instruments have been designed and built during the last couple of years: the Laser Ionization Mass Nanoscope (LIMAS) at Hokkaido University and the Chicago Instrument for Laser Ionization (CHILI) at The University of Chicago. When they become operational, we will be able to learn much more about nucleosynthesis in stars.