Determination of the voltage applied to x‐ray tubes from the bremsstrahlung spectrum obtained with a silicon PIN photodiode
Abstract
This work describes a methodology for the obtainment of the electron accelerating potential (kVp) applied to an x‐ray tube, through the determination of the end point of the energy spectrum of the radiation emitted by the tube. The measurements have been performed utilizing alternatively two silicon PIN photodiodes, directly irradiated by the x‐ray beam. Both were operated at room temperature, with low bias, so avoiding the drawbacks presented by photomultiplier tubes and germanium detectors. The energy calibration of the system was performed with X‐ and 
‐emitter radioactive sources, which makes the method absolute. Each kVp value was determined by means of a linear regression in the end of the spectrum, to give, simultaneously, a good fit of the straight line to the experimental data and a low standard deviation for the kVp value. Results of the measurements carried out with an x‐ray tube connected to a three‐phase generator, using additional filtration between 1.5 and 4.0 mm of Cu, are presented. This filtration was used in order to minimize the contribution of low energy photons and to reduce pulse pile‐up. Errors determined for the values of kVp are between 0.06 and 0.16 kV, in the potential range from 50 to 100 kV. As an example, the methodology has been applied in the verification of the secondary calibration of a voltage divider, utilized, by its turn, in the tertiary calibration of noninvasive kVp meters. All intrinsic sources of errors involved in the process are discussed and evaluated.
Number of times cited: 15
- L. Abbene and S. Del Sordo, CdTe Detectors, Comprehensive Biomedical Physics, 10.1016/B978-0-444-53632-7.00619-5, (285-314), (2014).
- Nancy K. Umisedo, Roseli Künzel, Emico Okuno, Elisabeth M. Yoshimura, Anna Luiza M.C. Malthez and Marcelo B. Freitas, Spectroscopy of the gamma and X ray leakage radiation from the built-in sources of a Risø TL/OSL reader, Radiation Measurements, 71, (197), (2014).
- C.H. Murata, D.C. Fernandes, N.C. Lavínia, L.V.E Caldas, S.R Pires and R.B. Medeiros, The performance of a prototype device designed to evaluate general quality parameters of X-ray equipment, Radiation Physics and Chemistry, 95, (101), (2014).
- M G David, E J Pires, M A Bernal, J G Peixoto and C E Dealmeida, Experimental and Monte Carlo-simulated spectra of standard mammography-quality beams, The British Journal of Radiology, 85, 1013, (629), (2012).
- L. Abbene, G. Gerardi, F. Principato, S. Del Sordo, R. Ienzi and G. Raso, High‐rate x‐ray spectroscopy in mammography with a CdTe detector: A digital pulse processing approach, Medical Physics, 37, 12, (6147-6156), (2010).
- M. Krmar, N. Bucalović, M. Baucal and N. Jovančević, Possible use of CdTe detectors in kVp monitoring of diagnostic X-ray tubes, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 622, 1, (256), (2010).
- L. Mondragón-Contreras, F.J. Ramírez-Jiménez, J.M. García-Hernández, M.A. Torres-Bribiesca, R. López-Callejas, E.F. Aguilera-Reyes, R. Peña-Eguiluz, H. López-Valdivia and H. Carrasco-Abrego, Application of PIN photodiodes on the detection of X-rays generated in an electron accelerator, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 609, 2-3, (187), (2009).
- Paulo R. Costa, Denise Y. Nersissian, Fernanda C. Salvador, Patr??cia B. Rio and Linda V. E. Caldas, GENERATION OF CALIBRATED TUNGSTEN TARGET X-RAY SPECTRA: MODIFIED TBC MODEL, Health Physics, 92, 1, (24), (2007).
- M. Krmar, S. Shukla and K. Ganezer, Some aspects involving the use of CdTe for finding end-point energies in diagnostic radiology, Applied Radiation and Isotopes, 64, 5, (584), (2006).
- Roseli Künzel, Silvio Bruni Herdade, Ricardo Andrade Terini and Paulo Roberto Costa, X‐ray spectroscopy in mammography with a silicon PIN photodiode with application to the measurement of tube voltage, Medical Physics, 31, 11, (2996-3003), (2004).
- R A Terini, M A G Pereira, R Künzel, P R Costa and S B Herdade, Comprehensive analysis of the spectrometric determination of voltage applied to X-ray tubes in the radiography and mammography energy ranges using a silicon PIN photodiode, The British Journal of Radiology, 77, 917, (395), (2004).
- G. Baldazzi, T. Bernardi, J.E. Fernandez, P. Ferrari, P.L. Rossi, G. Testoni and R. Zannoli, X-rays spectroscopy with a portable Compton selection chamber: detector design and results, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 10.1016/S0168-583X(03)01576-3, 213, (223-226), (2004).
- Takahiko Aoyama, Shuji Koyama and Chiyo Kawaura, An in‐phantom dosimetry system using pin silicon photodiode radiation sensors for measuring organ doses in x‐ray CT and other diagnostic radiology, Medical Physics, 29, 7, (1504-1510), (2002).
- Paulo R. Costa and Linda V. E. Caldas, Evaluation of protective shielding thickness for diagnostic radiology rooms: Theory and computer simulation, Medical Physics, 29, 1, (73), (2001).
- Leonardo Abbene, Gaetano Gerardi, Fabio Principato, Stefano Del Sordo and Giuseppe Raso, Direct Measurement of Mammographic X-Ray Spectra with a Digital CdTe Detection System, Sensors, 10.3390/s120608390, 12, 12, (8390-8404), (2012).
