Tree Code for Collision Detection of Large Numbers of Particles Application for the Breit-Wheeler Process

TL;DR

This paper introduces a tree code method utilizing bounding volume hierarchies to efficiently detect collisions among large numbers of particles, enabling detailed analysis of high-density particle interactions such as photon beam collisions leading to pair creation.

Contribution

The paper presents a novel application of tree code collision detection to analyze photon beam interactions and pair creation, improving efficiency over classical methods.

Findings

Efficient collision detection for large particle numbers.

Application to photon beam collision analysis.

Insights into electron-positron pair creation.

Abstract

Collision detection of a large number N of particles can be challenging. Directly testing N particles for collision among each other leads to N 2 queries. Especially in scenarios, where fast, densely packed particles interact, challenges arise for classical methods like Particle-in-Cell or Monte-Carlo. Modern collision detection methods utilising bounding volume hierarchies are suitable to overcome these challenges and allow a detailed analysis of the interaction of large number of particles. This approach is applied to the analysis of the collision of two photon beams leading to the creation of electron-positron pairs.