Performance of an optical TPC Geant4 simulation with opticks GPU-accelerated photon propagation

Abstract We investigate the performance of , a 7.5 GPU-accelerated photon propagation tool compared with a single-threaded simulation. We compare the simulations using an improved model of the gaseous time projection chamber. Performance results suggest that improves simulation speeds by between $$58.47\pm {0.02}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>58.47</mml:mn> <mml:mo>±</mml:mo> <mml:mrow> <mml:mn>0.02</mml:mn> </mml:mrow> </mml:mrow> </mml:math> and $$181.39\pm {0.28}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>181.39</mml:mn> <mml:mo>±</mml:mo> <mml:mrow> <mml:mn>0.28</mml:mn> </mml:mrow> </mml:mrow> </mml:math> times relative to a CPU-only simulation and these results vary between different types of GPU and CPU. A detailed comparison shows that the number of detected photons, along with their times and wavelengths, are in good agreement between and .