Oxygen Isotope Exchange Between Molten Silicate Spherules and Ambient Water Vapor with Nonzero Relative Velocity: Implication for Chondrule Formation EnvironmentOPEN ACCESS 

Sota Arakawa, Daiki Yamamoto, Takayuki Ushikubo, Hiroaki Kaneko, Hidekazu Tanaka, Shigenobu Hirose, Taishi Nakamoto

Accepted for publication in Icarus


Update (28 June 2023): Icarus LINK

“Oxygen isotope compositions of chondrules reflect the environment of chondrule formation and its spatial and temporal variations. Here, we present a theoretical model of oxygen isotope exchange reaction between molten silicate spherules and ambient water vapor with finite relative velocity. We found a new phenomenon, that is, mass-dependent fractionation caused by isotope exchange with ambient vapor moving with nonzero relative velocity. We also discussed the plausible condition for chondrule formation from the point of view of oxygen isotope compositions. Our findings indicate that the relative velocity between chondrules and ambient vapor would be lower than several 100 m/s when chondrules crystallized.”