Speaker
Description
We present a summary of cross sections for electron scattering on H$_2$ for fusion and astrophysical plasma-modelling applications, calculated using the molecular convergent close-coupling (MCCC) method. Accurate collisional-radiative modelling requires the input of cross sections for numerous processes, including elastic scattering, ionisation, and excitation, considering a large number of different initial and final states. For molecules, resolution in the vibrational and rotational levels is often required.
Over the last few decades, the CCC method has been established as one of the world’s most accurate techniques for calculating collision cross sections, with its particular strength in being able to solve the scattering equations over the entire incident energy range for most processes of practical interest. The application to scattering on molecules with a focus on calculating rovibrationally-resolved cross sections has led to the largest set of collision data ever produced for any scattering system. A dedicated database (mccc-db.org) is established for the data also available from the IAEA database CollisionDB.
In this poster we showcase results for electron collisions with H$_2$, with examples of applications in fusion and astrophysical plasma models. Comparisons are made with previously available data, wherever available. However, the majority of data we have produced is the first of its kind. The attached figure compares the results of a collisional-radiative (CR) model for the triplet system of H$_2$ using MCCC cross sections [ 1] as well as cross sections from two previous datasets [2,3] with measurements [4]. The CR model using MCCC cross sections yields much better agreement with experiment.
Fig. 1 Application of MCCC cross sections in a collisional-radiative model for H$_2$.
[ 1] L. H. Scarlett et. al., Atom. Data Nucl. Data Tables 137, 101361 (2021)
[2] R. K. Janev et. al., "Collision processes in low-temperature hydrogen plasmas", Jülich (2003)
[3] Miles et. al., J. Appl. Phys. 43, 678 (1972)
[4] Wünderlich et. al., J. Phys. D: Appl. Phys 54, 115201 (2021)
