SUET180: Fano Cavity Test of Proton Transport in Monte Carlo Codes Running On GPU and Xeon Phi
Abstract
Purpose: In proton dose calculation, clinically compatible speeds are now achieved with Monte Carlo codes (MC) that combine 1) adequate simplifications in the physics of transport and 2) the use of hardware architectures enabling massive parallel computing (like GPUs). However, the uncertainties related to the transport algorithms used in these codes must be kept minimal. Such algorithms can be checked with the socalled “Fano cavity test”. We implemented the test in two codes that run on specific hardware: gPMC on an nVidia GPU and MCsquare on an Intel Xeon Phi (60 cores). Methods: gPMC and MCsquare are designed for transporting protons in CT geometries. Both codes use the method of fictitious interaction to sample the steplength for each transport step. The considered geometry is a water cavity (2×2×0.2 cm{sup 3}, 0.001 g/cm{sup 3}) in a 10×10×50 cm{sup 3} water phantom (1 g/cm{sup 3}). CPE in the cavity is established by generating protons over the phantom volume with a uniform momentum (energy E) and a uniform intensity per unit mass I. Assuming no nuclear reactions and no generation of other secondaries, the computed cavity dose should equal IE, according to Fano's theorem. Both codes were tested for initial proton energies ofmore »
 Authors:
 Universite catholique de Louvain, Brussels, Brussels (Belgium)
 Massachusetts General Hospital, Boston, MA (United States)
 The University of Texas Southwestern Medical Ctr, Dallas, TX (United States)
 Publication Date:
 OSTI Identifier:
 22339927
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Medical Physics; Journal Volume: 41; Journal Issue: 6; Other Information: (c) 2014 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 60 APPLIED LIFE SCIENCES; ACCURACY; ALGORITHMS; AMINO ACIDS; MONTE CARLO METHOD; NUCLEAR REACTIONS; PHANTOMS; PROTON TRANSPORT
Citation Formats
Sterpin, E, Sorriaux, J, Souris, K, Lee, J, Vynckier, S, Schuemann, J, Paganetti, H, Jia, X, and Jiang, S. SUET180: Fano Cavity Test of Proton Transport in Monte Carlo Codes Running On GPU and Xeon Phi. United States: N. p., 2014.
Web. doi:10.1118/1.4888510.
Sterpin, E, Sorriaux, J, Souris, K, Lee, J, Vynckier, S, Schuemann, J, Paganetti, H, Jia, X, & Jiang, S. SUET180: Fano Cavity Test of Proton Transport in Monte Carlo Codes Running On GPU and Xeon Phi. United States. doi:10.1118/1.4888510.
Sterpin, E, Sorriaux, J, Souris, K, Lee, J, Vynckier, S, Schuemann, J, Paganetti, H, Jia, X, and Jiang, S. Sun .
"SUET180: Fano Cavity Test of Proton Transport in Monte Carlo Codes Running On GPU and Xeon Phi". United States.
doi:10.1118/1.4888510.
@article{osti_22339927,
title = {SUET180: Fano Cavity Test of Proton Transport in Monte Carlo Codes Running On GPU and Xeon Phi},
author = {Sterpin, E and Sorriaux, J and Souris, K and Lee, J and Vynckier, S and Schuemann, J and Paganetti, H and Jia, X and Jiang, S},
abstractNote = {Purpose: In proton dose calculation, clinically compatible speeds are now achieved with Monte Carlo codes (MC) that combine 1) adequate simplifications in the physics of transport and 2) the use of hardware architectures enabling massive parallel computing (like GPUs). However, the uncertainties related to the transport algorithms used in these codes must be kept minimal. Such algorithms can be checked with the socalled “Fano cavity test”. We implemented the test in two codes that run on specific hardware: gPMC on an nVidia GPU and MCsquare on an Intel Xeon Phi (60 cores). Methods: gPMC and MCsquare are designed for transporting protons in CT geometries. Both codes use the method of fictitious interaction to sample the steplength for each transport step. The considered geometry is a water cavity (2×2×0.2 cm{sup 3}, 0.001 g/cm{sup 3}) in a 10×10×50 cm{sup 3} water phantom (1 g/cm{sup 3}). CPE in the cavity is established by generating protons over the phantom volume with a uniform momentum (energy E) and a uniform intensity per unit mass I. Assuming no nuclear reactions and no generation of other secondaries, the computed cavity dose should equal IE, according to Fano's theorem. Both codes were tested for initial proton energies of 50, 100, and 200 MeV. Results: For all energies, gPMC and MCsquare are within 0.3 and 0.2 % of the theoretical value IE, respectively (0.1% standard deviation). Singleprecision computations (instead of double) increased the error by about 0.1% in MCsquare. Conclusion: Despite the simplifications in the physics of transport, both gPMC and MCsquare successfully pass the Fano test. This ensures optimal accuracy of the codes for clinical applications within the uncertainties on the underlying physical models. It also opens the path to other applications of these codes, like the simulation of ion chamber response.},
doi = {10.1118/1.4888510},
journal = {Medical Physics},
number = 6,
volume = 41,
place = {United States},
year = {Sun Jun 01 00:00:00 EDT 2014},
month = {Sun Jun 01 00:00:00 EDT 2014}
}

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A Fano cavity test for Monte Carlo proton transport algorithms
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A Fano cavity test for Monte Carlo proton transport algorithms
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SUET521: Investigation of the Uncertainties Involved in Secondary Neutron/gamma Production in Geant4/MCNP6 Monte Carlo Codes for Proton Therapy Application
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