Determination of the Electron Beam Parameters for a 4-MV Biological X-ray Irradiator
- PDF / 318,626 Bytes
- 4 Pages / 595.22 x 842 pts (A4) Page_size
- 6 Downloads / 166 Views
Determination of the Electron Beam Parameters for a 4-MV Biological X-ray Irradiator Kyoung Won Jang, Manwoo Lee, Heuijin Lim, Sang Koo Kang and Dong Hyeok Jeong∗ Research Center, Dongnam Institute of Radiological & Medical Sciences, Busan 46033, Korea (Received 8 January 2020; accepted 10 April 2020) In this study, low-energy electron linear accelerators (LINACs) were proposed for applications in biological studies to replace the gamma-ray irradiators. An important parameter in biological research involves the precise dose delivery to the biological sample at an appropriate dose rate, so the beam parameters of the LINACs should be determined so as to satisfy the required dose rate. A cost effective practical LINAC design can be achieved by using the determined beam parameters. Pulsed electron beam parameters, including the pulsed beam current, pulse width, and pulse frequency, as functions of the dose rate for irradiated X-rays were examined via the Monte Carlo N-Particle transport code. Optimum ranges for pulsed electron beams were evaluated to deliver a dose rate exceeding 4 Gy/min at a distance of 30 cm from the target. Keywords: LINAC, Pulsed electron beam, Dose rate DOI: 10.3938/jkps.77.443
I. INTRODUCTION Gamma-ray irradiators using high-activity radioisotopes are used in biological studies to examine the radiation effect at the cellular level [1]. In preclinical studies, high dose irradiations for experimental cells and animals are generally performed to investigate the effect of radiation on normal and cancer cells in terms of cell damage or death [2]. However, disadvantages in the use of gamma-ray irradiators include the periodic exchange of high-price sources and management of high-risk radioisotopes. As a way to overcome the aforementioned disadvantages, a low-energy electron linear accelerator (LINAC) can be examined in applications of preclinical studies. One of the important parameters in biological studies corresponds to precise dose delivery to the sample with an appropriate dose rate; thus, the accelerator beam parameters must be determined from the predetermined dose rate. For accelerator components, determining the electron beam parameters for the practical design and fabrication of a cost-effective accelerator is important because the specifications of the electron gun, magnetron or klystron, and high-voltage pulse modulator system are related to the electron beam parameters. However, estimating the relation between the X-rays generated from the electron beam and the dose absorbed by the biological sample at an arbitrary distance from the target is complicated. An empirical formula to determine the dose rate at a distance of 1 m is used in industrial appli∗ E-mail:
[email protected]
pISSN:0374-4884/eISSN:1976-8524
cations [3–5]. However, that is not enough to calculate the X-ray output, exactly from the formula, because the X-ray output depends on the geometry of the irradiator head consisting of various components including the target system. Alternatively, Monte Carlo simulations can be appli
Data Loading...
