Related Experiment Video
Updated: Mar 29, 2026

Use of a Linear Accelerator for Conducting In Vitro Radiobiology Experiments
Published on: May 26, 2019
DOSE AND GAMMA-RAY SPECTRA FROM NEUTRON-INDUCED RADIOACTIVITY IN MEDICAL LINEAR ACCELERATORS FOLLOWING HIGH-ENERGY
S Keehan1, M L Taylor2, R L Smith2,3
1School of Applied Sciences, RMIT University, Melbourne, Australia stephanie.keehan@rmit.edu.au.
Abstract:
Production of radioisotopes in medical linear accelerators (linacs) is of concern when the beam energy exceeds the threshold for the photonuclear interaction. Staff and patients may receive a radiation dose as a result of the induced radioactivity in the linac. Gamma-ray spectroscopy was used to identify the isotopes produced following the delivery of 18 MV photon beams from a Varian 21EX and an Elekta Synergy. The prominent radioisotopes produced include 187W, 63Zn, 56Mn, 24Na and 28Al in both linac models. The dose rate was measured at the beam exit window (12.6 µSv in the first 10 min) following 18 MV total body irradiation (TBI) beams. For a throughput of 24 TBI patients per year, staff members are estimated to receive an annual dose of up to 750 μSv at the patient location. This can be further reduced to 65 μSv by closing the jaws before re-entering the treatment bunker.
More Related Videos
Related Concept Videos
Biological Effects of Radiation
Types of Radioactivity
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
Nuclear Transmutation
Isotopes and Radioisotopes
An isotope containing...
Absorption of Radiation
Positron Emission Tomography
One of the main requirements of a PET scan is a positron-emitting radioisotope, which is produced in a cyclotron and then attached to a substance used by the part of the body...

