Project title: Charge transfer in stars and supernovae
Main applicant: Paul Barklem, Division of Astronomy and Space Physics
Grant amount: 3 120 000 SEK for the period 2021-2024
A key insight from quantum mechanics is the importance of processes involving electron rearrangement, such as charge transfer (C T) in collisions between atoms. In dilute plasmas such as those often observed in astrophysics, (e.g. cometary comae, planetary and stellar atmospheres, nebulae, the interstellar medium, supernovae) such processes are often efficient, and greatly affect spectra of astrophysical objects. In this project, I will study C T involving neutral atoms, singly ionised atoms, and negative ions. The overarching goal is to improve the reliability and accuracy of modelling of the spectra of stars and supernovae, and thus the accuracy with which we can study chemical evolution in the universe.
Specifically, I will theoretically and experimentally study C T processes involving hydrogen atoms of the form:
A+ + H- → A(j) + H,
known to be important in modelling spectra of stars and interpreting their chemical composition.
I will theoretically study charge transfer processes important in supernovae (SNe) ejecta spectra. In particular, I will study:
C + O+ → C+ + O(1D)
in detail using full quantum methods. This process is important in measuring oxygen in SNe. I will also attempt to develop a model that can produce large amounts of data at moderate accuracy for the poorly understood general process
A + B+ → A+ + B(j).
This is important for modelling SNe, and other astrophysical objects such as kilonovae, and probing their production of chemical elements.
