scholarly journals Modeling and Reconstruction Strategy for Compton Scattering Tomography with Scintillation Crystals

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 641
Author(s):  
Lorenz Kuger ◽  
Gael Rigaud
Keyword(s):  
Compton Scattering ◽  
Electron Density ◽  
Computerized Tomography ◽  
Scattered Radiation ◽  
Compton Effect ◽  
Medical Applications ◽  
General Strategy ◽  
Scintillation Crystals ◽  
Reconstruction Strategy ◽  
Variable Energy

The recent development of energy-resolved scintillation crystals opens the way to build novel imaging concepts based on the variable energy. Among them, Compton scattering tomography (CST) is one of the most ambitious concepts. Akin to Computerized Tomography (CT), it consists in probing the attenuation map of an object of interest using external ionizing sources but strives to exploit the scattered radiation as an imaging agent. For medical applications, the scattered radiation represents 70 to 80% when the energy of the source is larger than 100 keV and results from the Compton effect. This phenomenon stands for the collision of a photon with an electron and rules the change of course and loss of energy undergone by the photon. In this article, we propose a modeling for the scattered radiation assuming polychromatic sources such as 60Co and scintillation crystals such as LBC:Ce. Further, we design a general strategy for reconstructing the electron density of the target specimen. Our results are illustrated for toy objects.

The resonant scattering of gamma radiation from lead isotopes

1978 ◽  
Vol 56 (8) ◽  
pp. 1021-1036 ◽  
Author(s):  
J. W. Knowles ◽  
A. M. Khan ◽  
W. F. Mills
Keyword(s):  
Gamma Radiation ◽  
Compton Scattering ◽  
Scattered Radiation ◽  
Lead Isotopes ◽  
Resonant Scattering ◽  
Aluminum Plate ◽  
Γ Radiation ◽  
Energy Beam ◽  
Scattering Measurements ◽  
Variable Energy

The scattering of gamma radiation from different isotopic mixtures of lead has been measured between 4.7 and 8.3 MeV with a variable energy beam with 175 keV resolution obtained by Compton scattering (n,γ) radiation of nickel from a curved aluminum plate. The elastically scattered radiation was detected with a 12.5 cm diameter, 12.5 cm long NaI(Tl) and with 27 or 49 cm3 Ge(Li) detectors located at scattering angles of 135° and 90°, respectively. Relative scattering measurements from targets of natural lead, radio-lead, and lead enriched in 208Pb show that the most prominent peaks of natural lead are in 208Pb at 7332.6 ± 1.3, 7087.7 ± 4.6, 7064.4 ± 3.5, 6721.0 ± 1.8, 5507.6 ± 1.8, 5292.6 ± 3.3, 4836.5 ± 4.6 keV. Measurements of resonant scattering and resonant self-absorption of the more intense scattered radiations provide information on level widths.

scholarly journals The compton scattering and the new statistics

1929 ◽  
Vol 125 (796) ◽  
pp. 231-237 ◽  
Keyword(s):  
Compton Scattering ◽  
Electron Gas ◽  
Compton Effect ◽  
Maxwellian Distribution ◽  
Great Success ◽  
Free Electrons ◽  
Electron Theory ◽  
Conservation Of Momentum ◽  
New Statistics ◽  
Energy Principles

Great success has been achieved by Sommerfeld in the electron theory of metals by assuming that there are free electrons in them which obey the Fermi-Dirac statistics. It has been assumed in the case of univalent metals that on the average one electron per atom is free. In general, however, the valency electrons can be considered as free. These free electrons will take part in the Compton scattering. The analysis of such a Compton effect reduces to the analysis of the collisions between radiation quanta and an electron gas. The general features of such a scattering was first considered by Dirac. But he has assumed a Maxwellian distribution for the electrons which will not be applicable to the case under consideration, because the electrons in a conductor being degenerate do not obey the Maxwell's law, but the Fermian distribution. In considering such a process we take it that the conservation of momentum and energy principles are satisfied for each particular collision just as in Compton's theory—only we are here dealing with moving electrons instead of stationary electrons which Compton considers. Thus electrons of different momenta components will produce different Compton shifts, and the intensity of any particular shift will depend on the number of electrons in that state. Thus we have to average for the radiation falling on an assembly of electrons whose momenta are distributed according to the Fermi-Dirac law.

Electron-density measurements in bone using dual-energy compton scattering

Bone ◽  
1985 ◽  
Vol 6 (5) ◽  
pp. 405-405
Author(s):  
A.L. Huddleston ◽  
Jay P. Sackler
Keyword(s):  
Compton Scattering ◽  
Electron Density ◽  
Dual Energy ◽  
Density Measurements

X-ray Excitation of Thermal Spikes

1973 ◽  
Vol 28 (5) ◽  
pp. 679-681 ◽  
Author(s):  
R. J. Weiss
Keyword(s):  
Compton Scattering ◽  
Convenient Method ◽  
Impulse Approximation ◽  
Compton Effect ◽  
Single Atom ◽  
Thermal Spike ◽  
X Ray ◽  
X Ray Scattering ◽  
Scattering Measurements ◽  
Amorphous Media

For x-ray scattering from amorphous media at large sin θ/λ (> 1.00 Å-1) momentum and energy is either imparted to a single electron (Compton effect) or to a single atom (Thermal Spike effect). In both cases the impulse approximation provides a convenient method for treating the scattering. Measurements of the ratio of Thermal Spike scattering to Compton scattering were made on paraffin.

scholarly journals On the intensity of total scattering of X-rays

1929 ◽  
Vol 124 (793) ◽  
pp. 119-142 ◽  
Keyword(s):  
High Frequency ◽  
Scattered Radiation ◽  
Wave Length ◽  
Incident Radiation ◽  
Compton Effect ◽  
X Rays ◽  
Free Electrons ◽  
Scattering Angle ◽  
Total Scattering ◽  
Monatomic Gas

We shall here investigate theoretically the intensity of total scattering of X-rays by atoms distributed at random, e. g. , the scattering by the atoms of a monatomic gas. In the scattered radiation we shall not include the characteristic X-rays excited by the incident radiation. The scattered radiation consists then partly of radiation having the same frequency as the incident radiation (coherent scattered radiation) and partly of radiation having other frequencies (incoherent scattered radiation). For sufficiently high frequency of the incident radiation the incoherent scattered radiation is then nearly monochromatic for a given scattering angle, and consists practically entirely of radiation whose wave-length and intensity is given by the formulæ for the Compton effect for the scattering by free electrons. Generally, however, it must be taken into account that several frequencies occur in the scattered radiation for each direction of scattering. The total intensity of the scattered radiation for a given direction has therefore to be taken as a sum of the intensities of the different components, each having a definite frequency. General expressions for the scattered radiation are given by a scattering formula derived by one of us. In this formula “relativity corrections” are neglected; for the intensity of scattering in the Compton effect for free electrons, this approximation, and a further one which we also make, lead to the classical Thomson formula. This means that our intensity formula gives a useful approximation only if the incident radiation is not too hard ( e. g. , has a wave-length not shorter than about 1 Å., in which case the error arising from the approximation just mentioned should not exceed a few per cent.).

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