The Origin of Presolar Silica Grains in AGB Stars
No Thumbnail Available
Meeting name
Sponsors
Date
Journal Title
Format
Article
Subject
Abstract
We have found two presolar silica grains in ALH A77307, which exhibit excesses in 17O but are normal in 18O. Silicon-oxide grains probably form during rapid cooling under non-equilibrium conditions in O-rich AGB stars with low Mg/Si ratios.