Helium-3 and Helium-4 acceleration by high power laser pulses for hadron therapy

TL;DR

This paper explores laser-driven acceleration of helium-3 and helium-4 ions for hadron therapy, demonstrating that helium ions can be effectively accelerated to therapeutic energies using high-power laser pulses, with helium-3 requiring less laser power.

Contribution

It investigates two laser acceleration mechanisms for helium ions and shows helium-3's advantage in reducing laser power needs for therapy applications.

Findings

Helium ions can be accelerated to 250 MeV per nucleon with PW-class lasers.

Helium-3 ions require less laser power than helium-4 for the same energy.

Both acceleration mechanisms are effective for hadron therapy requirements.

Abstract

The laser driven acceleration of ions is considered a promising candidate for an ion source for hadron therapy of oncological diseases. Though proton and carbon ion sources are conventionally used for therapy, other light ions can also be utilized. Whereas carbon ions require 400 MeV per nucleon to reach the same penetration depth as 250 MeV protons, helium ions require only 250 MeV per nucleon, which is the lowest energy per nucleon among the light ions. This fact along with the larger biological damage to cancer cells achieved by helium ions, than that by protons, makes this species an interesting candidate for the laser driven ion source. Two mechanisms (Magnetic Vortex Acceleration and hole-boring Radiation Pressure Acceleration) of PW-class laser driven ion acceleration from liquid and gaseous helium targets are studied with the goal of producing 250 MeV per nucleon helium ion beams that meet the hadron therapy requirements. We show that He3 ions, having almost the same penetration depth as He4 with the same energy per nucleon, require less laser power to be accelerated to the required energy for the hadron therapy.