This paper describes experimental comparison of the sensitivity of the NBS P2-4 ionization chamber and a replica of Wilson's Quantameter. The sensitivity ratios are used to compare calorimetric measurements of total x-ray beam energy made at the NBS and in the USSR between 20 and 90 MeV. The agreement is within the combined errors, but the source of an apparent 2 percent systematic difference has not been found.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6478152 | PMC |
http://dx.doi.org/10.6028/jres.068A.070 | DOI Listing |
Int J Radiat Biol
August 2024
Department of Physics, Hakim Sabzevari University, Sabzeoar, Iran.
Introduction: The need for accurate relative biological effectiveness (RBE) estimation for low energy therapeutic X-rays (corresponding to 50 kV nominal energy of a commercial low-energy IORT system (INTRABEAM)) is a crucial issue due to increased radiobiological effects, respect to high energy photons. Modeling of radiation-induced DNA damage through Monte Carlo (MC) simulation approaches can give useful information. Hence, this study aimed to evaluate and compare RBE of low energy therapeutic X-rays using Geant4-DNA toolkit and Monte Carlo damage simulation (MCDS) code.
View Article and Find Full Text PDFSci Rep
October 2022
Albert Einstein Center for Fundamental Physics (AEC), Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland.
Phys Med Biol
March 2022
MAASTRO, Doctor Tanslaan 12, Maastricht, 6202 NA, NETHERLANDS.
Objective Proton therapy is gaining popularity because of the improved dose delivery over conventional radiation therapy. The secondary dose to healthy tissues is dominated by secondary neutrons. Commercial rem-counters are valuable instruments for the on-line assessment of neutron ambient dose equivalent (H*(10)).
View Article and Find Full Text PDFLife (Basel)
December 2021
Department of Physics, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11642, Saudi Arabia.
This paper presents guidelines for the calibration of radiation beams that were issued by the International Atomic Energy Agency (IAEA TRS 398), the American Association of Physicists in Medicine (AAPM TG 51) and the German task group (DIN 6800-2). These protocols are based on the use of an ionization chamber calibrated in terms of absorbed dose to water in a standard laboratory's reference quality beam, where the previous protocols were based on air kerma standards. This study aims to determine uncertainties in dosimetry for electron beam radiotherapy using internationally established high-energy radiotherapy beam calibration standards.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
December 2021
Department of Medical Physics, Medical Radiation Research Center, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin.
Purpose: Accurate radiation dose is required to ensure reproducibility in establishing the radiobiological effect in biological systems among institutions. The dose should be the most precise and accurate parameter of the entire process. The goal is a system to provide uniform radiation dose verification among institutions that is traceable to the National Institute of Standards and Technology (NIST) through an Accredited Dosimetry Calibration Laboratory.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!