Contents lists available at ScienceDirect Radiation Physics and Chemistry journal homepage: www.elsevier.com/locate/radphyschem Reprint of “X-ray spectrometry applied for determination of linear attenuation coefcient of tissue-equivalent materials” Audrew Frimaio a, ⁎ , Bruna C. Nascimento b , Ramon M.M. Barrio b , Leticia L. Campos a , Paulo R. Costa b a IPEN - Instituto de Pesquisas Energéticas e Nucleares, Av. Prof. Lineu Prestes, 2242 - Butantã,São Paulo - SP - Brazil - 05508-000, São Paulo, Brazil b Instituto de Física/Universidade de São Paulo, São Paulo, Brazil ARTICLEINFO Keywords: Phantoms Tissue-equivalent Attenuation coefcient ABSTRACT Resin-basedmaterialsequivalenttowaterweredevelopedandfourdiferent samples were obtained. The linear attenuation coefcients of all samples was evaluated using X-ray spectrometry with primary and transmitted beamsusingvoltagesattherangingfrom60to120kV.Theexperimentalmeasuredvalueswerecomparedwith theoretical reference values to water and with that obtained using the Least Square Method algorithm metho- dology (method applied to diagnostic radiology and radiotherapy). Our results show that diferences between themeasuredvaluesandthetargetμ(E)waslowerthan7%±0.3intheenergyrangefrom20to80keV.These results enable to consider that the material developed and produced is a good option to be used as a water- equivalent material and the experimental method adequate to its quantitative evaluation. 1. Introduction X-ray imaging is a powerful tool in modern Medicine and this modalityofimageproductionallowsthedetectionandinvestigationof several disease and other health problems. These modalities include general x-ray images, dental x-rays, mammography, fuoroscopy, in- terventionist radiology and computed tomography. However, the pro- duction of adequately qualifed images, which allows high probability of correct interpretation of a the disease under investigation by a trained radiologist, is a complex task involving technical and human limitations that must be correctly balanced in order to get the best outputoftheappliedmodality.Inthissense,itmustbeemphasizedthat theuseofionizingradiationforthispurposemustbecorrectlyjustifed andoptimized,sincethereisalwaysanassociatedriskinitsuse(World Health Organization and IAEA, 2013). The correlation between image qualityandthepotentiallyharmfulbiologicalefectsofradiationcanbe studied from the relationship between physical parameters of the image, such as contrast, noise, spatial resolution, and absorbed dose (Navarro et al., 2007). This correlation has been investigated and re- gistered in diagnostic radiology by the application of group or proce- dures known as Quality Control (QC), which is part of the Quality Assurance (QA) programs (Barrett et al., 2015; Pianykh, 2014; IEC, 2006). QC procedures are essential in modern diagnostic imaging to pro- vide reproducible information on image quality and dose (Azevedo etal.,2005)andtheyarerequiredbylawinseveralcountries(Agency, 2011). In practice, the part of the procedures are empirical im- plementation of experimental measurements which are dependent on special instrumentation and metrological defnitions (IAEA, 2007). An important group of this instrumentation has been historically called “phantoms”.Theseobjectsmimicstissues,partsofthehumanbodyand simulate specifc characteristics of the interaction of the ionizing ra- diation with the matter which are of interest for the QC measurements (Dewerd and Lawless, 2014). Thus, production of these phantoms de- pends on the manufacture of special tissue-equivalent materials for si- mulating specifc human tissues properties or materials of dosimetric interest. Diferent materials have been applied to simulate specifc physical properties of human tissues (Amini et al., 2018). These materials were developed to represent similar absorption and/or scattering properties of the real human tissue in order to allow the investigation of doses received by patients exposed to ionizing radiation. These tissue- https://doi.org/10.1016/j.radphyschem.2019.108553 Received 14 December 2018; Received in revised form 15 March 2019; Accepted 18 March 2019 DOI of original article: https://doi.org/10.1016/j.radphyschem.2019.03.021 Apublisher'serrorresultedinthisarticleappearinginthewrongissue.Thearticleisreprintedhereforthereader'sconvenienceandforthecontinuityofthespecial issue. For citation purposes, please use the original publication details; Radiation Physics and Chemistry, 160, pp. 89–95. ⁎ Correspondence to: Rua brasilio machado N:533, APTO 232 -D 09715140 Sao Bernardo do Campo, São Paulo, Brazil E-mail address: audrewf@terra.com.br (A. Frimaio). Radiation Physics and Chemistry 167 (2020) 108553 Available online 18 November 2019 0969-806X/ © 2019 Elsevier Ltd. All rights reserved. T