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Advanced Two Media (ATM) method for measurement of linear attenuation coefficient
Annals of Nuclear Energy, 2013Linear attenuation coefficient of irregular targets having unknown thickness (La, Pr, Nd, Gd, Tb, Ho and Er) and regular targets of known thickness (Mo, Ag, Sn, W and Pb) at 59.54 keV have been measured by using a new technique named Advanced Two Media (ATM) method.
Manoj Kumar Gupta +4 more
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Photon linear attenuation coefficients and water content of normal and pathological breast tissues
Applied Radiation and Isotopes, 1996Normal and pathological breast tissue samples were scanned using a Photon Transmission Tomography (PTT) technique in order to determine their averaged photon linear attenuation coefficients (mu). Subsequent to being freeze-dried the samples were examined, using a high purity germanium detector (HPGe) and the gamma-rays of energy 59.5 keV from an ...
J S, al-Bahri, N M, Spyrou
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Derivation of linear attenuation coefficients from CT numbers for low-energy photons
Physics in Medicine and Biology, 1999One can estimate photon attenuation properties from the CT number. In a standard method one assumes that the linear attenuation coefficient is proportional to electron density and ignores its nonlinear dependence on atomic number. When the photon energy is lower than about 50 keV, such as for brachytherapy applications, however, photoelectric ...
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The linear attenuation coefficients as features of multiple energy CT image classification
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2000Abstract We present in this paper an analysis of the linear attenuation coefficients as useful features of single and multiple energy CT images with the use of statistical pattern classification tools. We analyzed four CT images through two pointwise classifiers (the first classifier is based on the maximum-likelihood criterion and the second ...
M.R.P Homem +2 more
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Accuracy of linear attenuation coefficients measured with a photon counting CT system
2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC), 2012The purpose of our research is to develop a photon counting CT system with a semiconductor detector. The photon counting CT system enables us to decompose materials, and this information is useful to diagnose diseases. We developed a new CdTe detector that was able to measure x-rays with the count rate of 107 counts/sec/mm2 with four energy windows ...
Toru Kobayashi +5 more
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Physics in Medicine and Biology, 2010
The measurement of the linear attenuation coefficients of breast tissues is of fundamental importance in the field of breast x-ray diagnostic imaging. Different groups have evaluated the linear attenuation coefficients of breast tissues by carrying out direct attenuation measurements in which the specimens were thin and selected as homogeneous as ...
Chen, R. C. +10 more
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The measurement of the linear attenuation coefficients of breast tissues is of fundamental importance in the field of breast x-ray diagnostic imaging. Different groups have evaluated the linear attenuation coefficients of breast tissues by carrying out direct attenuation measurements in which the specimens were thin and selected as homogeneous as ...
Chen, R. C. +10 more
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Radiation Protection Dosimetry, 2012
The linear attenuation coefficient is an important factor in the correction of self-attenuation. In this study, a cone beam from a source of ∼1 μCi was utilised, not equipped with the collimator, and a complete geometric configuration was mathematically modelled. Samples of NaCl, Na2CO3 and (NH4)2SO4 were used to verify the mathematical model.
Chang-Jong, Kim +3 more
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The linear attenuation coefficient is an important factor in the correction of self-attenuation. In this study, a cone beam from a source of ∼1 μCi was utilised, not equipped with the collimator, and a complete geometric configuration was mathematically modelled. Samples of NaCl, Na2CO3 and (NH4)2SO4 were used to verify the mathematical model.
Chang-Jong, Kim +3 more
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Health Physics, 1999
Total linear attenuation coefficients of three tissue equivalent materials differing in their fat contents were experimentally determined for low energy photons in the range 13-51 keV. It is found that their variations with photon energy for each of these materials are describable by two distinct power functions with the validity ranges being (13-23 ...
R C, Sharma, T K, Haridasan
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Total linear attenuation coefficients of three tissue equivalent materials differing in their fat contents were experimentally determined for low energy photons in the range 13-51 keV. It is found that their variations with photon energy for each of these materials are describable by two distinct power functions with the validity ranges being (13-23 ...
R C, Sharma, T K, Haridasan
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Materials analysis using x-ray linear attenuation coefficient measurements at four photon energies
Physics in Medicine and Biology, 2005The analytical properties of an accurate parameterization scheme for the x-ray linear attenuation coefficient are examined. The parameterization utilizes an additive combination of N compositional- and energy-dependent coefficients. The former were derived from a parameterization of elemental cross-sections using a polynomial in atomic number.
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Radiation Measurements, 2010
Abstract The linear attenuation coefficients for normal (adipose and glandular) and neoplastic (benign and malignant) breast tissues were measured using monoenergetic X-ray beams at the energy range of 8–30 keV, combining narrow beam geometry and high energy resolution obtained using a diffracted X-ray beam.
A. Tomal +3 more
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Abstract The linear attenuation coefficients for normal (adipose and glandular) and neoplastic (benign and malignant) breast tissues were measured using monoenergetic X-ray beams at the energy range of 8–30 keV, combining narrow beam geometry and high energy resolution obtained using a diffracted X-ray beam.
A. Tomal +3 more
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