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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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