Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published August 2023 | Published
Journal Article Embargoed

Modeling the energetic tail of a dusty plasma's electron energy distribution and its effect on dust grain charge and behavior

  • 1. ROR icon California Institute of Technology


A model for a weakly ionized dusty plasma is proposed in which UV or x-ray radiation continuously creates free electrons at high energy, which then cool through collisions with a cold neutral gas before recombining. The transition of a free electron from high energy at birth to low energy at demise implies that the electron energy distribution is not the simple Maxwellian of an isolated system in thermal equilibrium, but instead has a high-energy tail that depends on the recombination time. This tail can have a major effect on dust grain charging because the flux of tail electrons can be substantial even if the density of tail electrons is small. Detailed analytic and numerical calculations of dust grain charging show that situations exist in which a small high-energy tail dominates charge behavior. This implies that dust grain charge in terrestrial and space dusty plasmas may be significantly underestimated if a Maxwellian distribution is assumed and the non-thermal dynamics are neglected.

Copyright and License

© 2023 Author(s). Published under an exclusive license by AIP Publishing.


This material is based upon the work supported by a NSF/DOE Partnership in Plasma Science and Engineering via DOE Award No. DE-SC0020079.


André Nicolov: Conceptualization (supporting); Data curation (lead); Formal analysis (lead); Investigation (lead); Methodology (equal); Writing – original draft (lead); Writing – review & editing (equal). Paul M. Bellan: Conceptualization (lead); Formal analysis (supporting); Funding acquisition (lead); Investigation (supporting); Methodology (equal); Resources (lead); Supervision (lead); Writing – review & editing (equal).

Data Availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Conflict of Interest

The authors have no conflicts to disclose.



The files will be made publicly available on August 1, 2024.

Additional details

October 26, 2023
October 26, 2023