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arXiv · 2503.00304

Simulating Negative Hydrogen ion acceleration in LINAC-4 using Unity 3D

D. M. C. M. K. Dissanayake·N. Wickramage·K. M. Liyanage·K. A. S. Lakshan
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Abstract

The Linear Accelerator 4 (LINAC 4) is designed to accelerate negative hydrogen ions to high energies for injection into the Large Hadron Collider (LHC), where it has been supplying proton beams since 2020. LINAC 4 accelerates negative hydrogen ions to 160 MeV. The accelerator pulses 400 microsecond bursts of negative hydrogen ions. A complex process is processed in this machine to achieve the required energy and simulating the machine is beneficial for improved understanding, visualization, educational purposes, and for training and skill development. Normally, high performance, specialized software is needed to simulate the intricate dynamics of ion acceleration. However, our goal is to develop an interactive, realtime model that effectively simulates the acceleration of negative H ions through the LINAC 4 stages by utilizing simulation and visualization capabilities of Unity 3D. In this study, Electric fields generated by each unit of LINAC 4 are assumed as known wave functions, and instantaneous velocity is calculated using fundamental physics laws. 3D structures were developed to approximate scale, and the user can control the frequency of the electric field to adjust the velocity, allowing the particle to reach the required energy level at the end. A time based pattern is used in the Chopper line, where the user can change the beam on time. Users can visualize the particle beam path and approximated graphical representation of the velocity variation in LINAC 4 under controllable electric fields and different time based chopping patterns generated by the chopper line. This simulation creates an accessible platform for students, researchers, and technicians to learn about processes of LINAC 4 in an interactive manner. It also guides users to better understand complex acceleration physics by allowing them to visualize the ion pathways, energy changes, and field interactions.

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D. M. C. M. K. Dissanayake, N. Wickramage, K. M. Liyanage, K. A. S. Lakshan. 2025-03-01. Simulating Negative Hydrogen ion acceleration in LINAC-4 using Unity 3D. https://arxiv.org/abs/2503.00304

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