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Neutron radiation effects on microcomputers in radiation therapy environments

Published online by Cambridge University Press:  08 September 2020

Josiah Herrington ,
Clara Ferreira ,
Yong Chen  and
Salahuddin Ahmad Open the ORCID record for Salahuddin Ahmad [Opens in a new window]
Josiah Herrington
Affiliation:
Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
Clara Ferreira
Affiliation:
Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN, USA
Yong Chen
Affiliation:
Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
Salahuddin Ahmad*
Affiliation:
Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
*
Author for correspondence: Salahuddin Ahmad, Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA. E-mail: salahuddin-ahmad@ouhsc.edu
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Abstract

Aim:

Microcomputers play an increasingly important role in the delivery of radiation therapy. Exposure to neutron irradiation can produce undesirable effects in modern microcomputers. The objective of this study is to measure acute and cumulative effects of neutron exposure of Intel-based microcomputers in photon and proton therapy treatment environments.

Materials and methods:

Multiple computers were irradiated with neutrons produced from MEVION S250 passive scattering proton therapy and from Varian 21EX Linear Accelerator photon therapy systems. The energy of the proton beam was 232 MeV and the photon beam energies were 6 and 18 MV. Rates of fatal errors in computer processing unit (CPU) cores were measured.

Results:

Varying rates of fatal system errors due to upsets in the CPU cores were observed. Post-exposure routine stress testing revealed no permanent hardware defects in the random access memory (RAM) or hard disk drive (HDD) of any tested systems. Microchip manufacturers fit increasingly high numbers of transistors in the same volume and the susceptibility to radiation thus increases.

Conclusions:

This work explores if the process size of a microchip is the dominant factor and also looked at the short- and long-term effects of neutron irradiation on modern microprocessors in a clinical environment. Additionally, methods of effective shielding are proposed.

Keywords

neutron radiation effectsmicrocomputersradiation environmentsradiotherapy
Type
Technical Note
Information
Journal of Radiotherapy in Practice , Volume 21 , Issue 1 , March 2022 , pp. 125 - 128
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Copyright
© The Author(s), 2020. Published by Cambridge University Press

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References

Newhauser, W D, Zhang, R. The physics of proton therapy. Phys Med Biol 2015; 60: R155–R209.CrossRefGoogle ScholarPubMed
Knoll, G F. Radiation Detection and Measurement, 2nd edition. Hoboken, NJ: John Wiley & Sons Inc., 1989.Google Scholar
Baumann, R C et al. Boron compounds as a dominant source of alpha particles in semiconductor devices. Proc. 33rd Int’l Reliability Physics Symp. (IRPS 95), IEEE Electron Devices Soc., 1995, pp. 297–302, doi: 10.1109/RELPHY.1995.513695.CrossRefGoogle Scholar
May, T C, Woods, M H. Alpha-particle-induced soft errors in dynamic memories. IEEE Trans Electron Dev 1979; 26: 2–9, doi: 10.1109/T-ED.1979.19370.CrossRefGoogle Scholar
Normand, E. Single event upset at ground level. IEEE Trans Nucl Sci 1996; 43: 2742–2750, doi: 10.1109/23.556861.CrossRefGoogle Scholar
Guenzer, C S, Wolicki, E A, Allas, R G. Single event upset of dynamic rams by neutrons and protons. IEEE Trans Nucl Sci 1979; 26: 5048–5052, doi: 10.1109/TNS.1979.4330270.CrossRefGoogle Scholar
Prusator, M, Ahmad, S, Chen, Y. Topas simulation of the Mevion S250 compact proton therapy unit. J Appl Clin Med Phys 2017; 18 (3): 88–95.CrossRefGoogle ScholarPubMed
Prusator, M T, Ahmad, S, Chen, Y. Shielding verification and neutron dose evaluation of the Mevion S250 proton therapy unit. J Appl Clin Med Phys 2018; 19 (2): 305–310.CrossRefGoogle ScholarPubMed
Herrington, J, Chen, Y, Ahmad, S, Ferreira, C. Susceptibility of microcomputers to malfunction induced by neutron radiation exposure in proton therapy environments. Med Phys 2017; 44 (6): 2873–2874.Google Scholar
Herrington, J, Ahmad, S, Chen, Y, Lewis, L, Ferreira, C. Vulnerability of microcomputer to instability induced by acute neutron radiation exposure: effects of CPU process size. Med Phys 2018; 45 (6): 2743.Google Scholar
Herrington, J, Chen, Y, Ahmad, S. Effects on modern microprocessors and method of shielding from neutron irradiation in photon therapy vaults. Poster presentation at the 62nd Joint AAPM-COMP Virtual (Due to COVID-19 Pandemic) Annual Meeting, 12–16 July, 2020.Google Scholar
Peterson, S W, Polf, J, Bues, M et al. Experimental validation of a Monte Carlo proton therapy nozzle model incorporating magnetically steered protons. Phys Med Biol 2009; 54 (10): 3217–3229.CrossRefGoogle ScholarPubMed
Ivanchenko, V, Dondero, P, Fioretti, V et al. Validation of Geant4 10.3 simulation of proton interaction for space radiation effects. Exp Astron 2017; 44 (3): 437–450.CrossRefGoogle Scholar