Experimental studies on a compact electron cyclotron resonance plasma x-ray source

Abstract

A compact electron cyclotron resonance plasma x-ray source, which has a potential use for medical imaging is presented in this article. In this article, the experimental system and the characterization studies on plasma and x ray are presented. Using a Langmuir probe, the plasma parameters are measured for different magnetic field profiles and gas pressures. The x-ray spectrum is obtained for various gas pressures and magnetic field profiles. In the x-ray spectrum, the Bremstrahlung radiation, peaking at 20–60 keV is observed and the final energy of the x ray is extended up to ∼200 keV. Thermo luminescence dosimeter (CaSO4 sample) is used for estimating the dose at the port and these results are presented for typical x-ray spectra. Using a teletector, the dose at the port for various coil current is measured and these are compared with the estimated dose obtained from the x-ray spectrum.

Analysis of x-ray spectrum obtained in electron cyclotron resonance x-ray source

“…[8][9][10] In recent years, x-ray source has been made based on ECR technique and the source is called ECR x-ray source. [11][12][13][14][15][16][17][18][19][20] In ECR x-ray source, electrons are accelerated continuously by matching the cyclotron frequency of the electrons to the microwave frequency ͑2.45 GHz͒. After gaining sufficient energy, these electrons collide with the target/cavity wall and produce bremsstrahlung x rays.…”

Ultrasoft x-ray emission from a linear ECR plasma source

“…In recent years, ECR plasma systems, designed in the form of microwave resonant cavities, have also been used as soft x-ray (SXR) sources [6][7][8][9][10]. These ECR plasma-based x-ray sources have the advantage over existing conventional x-ray sources in that, in ECR sources, hot filament (for electron emission) and high voltage power supplies are not required.…”

“…Various diagnostic tools for x-ray emission from the tokamak grade plasma are: a multichannel analyser with NaI(Tl) scintillator detector [7,8,10], with high purity Ge detector (HPGe) [9] for hard x-rays in the energy range 50 keV-10 MeV, solid state x-ray diodes such as silicon p-i-n diodes for SXRs in the energy range 800 eV-20 keV [17] and surface barrier diodes for SXRs in the energy range 300 eV-15 keV [18], etc. These detectors have good responsivity only in specific wavelength ranges as silicon detectors have good response in the range λ ∼ 50-500 Å and not outside this range because of a surface dead layer.…”

Note: Studies on target placement in TE111 cylindrical cavity of electron cyclotron resonance x-ray source for the enhancement of x-ray dose

“…[1][2][3][4][5] An ECR based x-ray source has been developed at RSD, IGCAR using TE 111 cylindrical cavity and 2.45 GHz microwave source. 6 In our earlier work, the plasma and x-ray characterization of the source have been carried out using Langmuir probe and x-ray spectrometers ͓based on NaI ͑Tl͒ and HPGe detectors͔, respectively. 6,7 The effective energy of x-ray source is made tunable with 40 and 70 keV and the potential use of the source for the calibration of thermoluminescent dosimeter ͑TLD͒ badges is explored in the low energy region.…”

“…6 In our earlier work, the plasma and x-ray characterization of the source have been carried out using Langmuir probe and x-ray spectrometers ͓based on NaI ͑Tl͒ and HPGe detectors͔, respectively. 6,7 The effective energy of x-ray source is made tunable with 40 and 70 keV and the potential use of the source for the calibration of thermoluminescent dosimeter ͑TLD͒ badges is explored in the low energy region. 8 Feasibility study for using the source for nondestructive testing and medical imaging applications has been demonstrated.…”