# Quantitative theory of channeling particle diffusion in transverse energy in the presence of nuclear scarrering and direct evaluation of dechanneling length

## TL;DR

This paper refines the theoretical understanding of particle diffusion in crystal channels, accounting for nuclear scattering, and provides a direct method to evaluate dechanneling lengths for different particles and energies.

## Contribution

It introduces a new equation for channeling particle diffusion that incorporates large-angle nuclear scattering and offers a direct evaluation method for dechanneling lengths.

## Key findings

- Dechanneling length is inapplicable for nuclear dechanneling of positively charged particles.
- Effective electron dechanneling length varies more than twice before reaching a constant asymptotic value.
- The refined equation reduces to a Sturm-Liouville problem, clarifying the origin and limitations of the dechanneling length concept.

## Abstract

A refined equation for channe;ing particle diffusion in transverse energy taking into consideration large-angle scattering by nuclei is suggested. This equation is reduced to the Sturm-Liouville problem allowing one to reveal both the origin and the limitations of the dechanneling length notion. The values of the latter is evaluated for both positively and negatively charged particles of various energies. It is also demonstrated that the dechanneling length notion is inapplicable for the nuclear dechanneling process of positively charged particles, while the effective electron dechanneling length of the latter vary more than twice converging to a constant assymptotic value at the depth exceeding the latter.