Analyzing emission spectra induced by a transmission-type X-ray tube with respect to target thickness and material using Monte Carlo simulation.

摘要

The purpose of this study is to determine the average X-ray energy needed to irradiate a target and, using MCNPX code, optimize the thickness of the target, the required beam current, and design variables such as the voltage of the X-ray tube. We analyzed energy spectra induced by a transmission-type X-ray tube for varying target thicknesses and materials. W, Au, and Mo were the target materials, results were compared for three different target thicknesses and tube voltages: 10 micrometers ,20 micrometers, and 3 0 micrometers and 80kVp, 100kVp, 160kVp after selecting the thickness and type of material of the target, energy spectra were obtained, the quantity and quality of X-rays was highest in the case of the Au target because the atomic number of Au is higher than those of W and Mo. We confirmed that the photon incidence increased with decreasing target thickness. Results due to changes in the tube voltage were as follows: releases of energy in the ranges of 20keV - 30keV, 40keV - 50keV, and 70keV - 80keV for tube voltages of 80kVp, 100kVp, and 160kVp, respectively. The energy release from a gold target is greater than that from a tungsten target. However, owing to the nature of the X-ray tube, and because the heat generation rate of the target is high, gold's high thermal conductivity makes it worthy of consideration as a target material.