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A scan artifact caused by a band of scattered photons.
Radiology, 1983Breast tissue often causes a ''hot'' artifact on a liver scan. This same extraneous feature also appears on brain scans and is caused by thick braids or toupees. With the use of a test object to simulate the liver and breast, the authors show that the artifact is due to scattered photons.
U Y, Ryo +3 more
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Russian Journal of Nondestructive Testing, 2021
A simulation model is proposed for evaluating nonmonoergeticity and scattering artifacts in computed tomography in parallel beam geometry using the example of inhomogeneous objects with axial symmetry. The modeling algorithm consists of a block for generating projections and a block for reconstructing images of sections of an object based on the ...
S. P. Osipov +4 more
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A simulation model is proposed for evaluating nonmonoergeticity and scattering artifacts in computed tomography in parallel beam geometry using the example of inhomogeneous objects with axial symmetry. The modeling algorithm consists of a block for generating projections and a block for reconstructing images of sections of an object based on the ...
S. P. Osipov +4 more
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Artifacts in helium atom surface scattering time-of-flight spectra
Physical Review B, 2003Artifacts have long been reported in the scattering of helium atoms from surfaces, particularly in the time-of-flight spectra used to study lattice dynamics. They are caused by elastic scattering of atoms in the low-intensity tails of the incident helium beam wave-vector distribution, which simulate inelastic scattering events. These ``deceptons'' have
E. A. Akhadov +6 more
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Analysis of scatter artifacts in cone-beam CT due to scattered radiation of metallic objects
15th International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, 2019Cone-beam computed tomography (CBCT) is a widely used technique for diagnostic or monitoring purposes. Compared to the traditional CT, a CBCT is more affected by scatter artifacts because of the large volume being irradiated by the beam. The research divulged in this paper is about the assessment of the influence that metallic implants may have on ...
Domenico Iuso +3 more
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Artifacts resulting from imaging in scattering media: a theoretical prediction
Optics Letters, 2009Scattering of illumination light from a laser is a severe problem especially when imaging in thick media. Although this effect occurs in nearly every imaging process, it can be well perceived and analyzed in configurations where the optical axes for illumination and detection are perpendicular to each other.
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Crustal Scattering and Some Artifacts in Receiver Function Images
Bulletin of the Seismological Society of America, 2004The existing 2D and 3D depth imaging approaches using multichannel teleseismic receiver functions (RFs) can result in significant artifacts caused by misinterpretation of signal-generated noise resulting from broadside scattering within the crust. A synthetic example using acquisition geometry of the 1993 Cascadia experiment shows that scattering of ...
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Scatter Correction Requirements for Likelihood-Based Attenuation Artifact Correction in PET
2006 IEEE Nuclear Science Symposium Conference Record, 2006Artifacts have been observed in CT-based, 511-keV attenuation images for PET attenuation correction. Artifact detection and correction algorithms are being developed based on the Poisson log likelihood function (LLF). The LLF quantifies the level of consistency between an activity and attenuation image pair and the measured emission sinogram.
C.M. Laymon +3 more
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Elemental concentration profile in ancient gold artifacts by ion beam scattering
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1996Abstract A technical study of the surface of some ancient gold based artifacts from South America (Colombia) is performed using ion beam techniques. Rutherford Backscattering Spectroscopy with protons and alpha particles was employed to establish the AuAgCu concentration depth profile of the items.
J.L. Ruvalcaba-Sil, G. Demortier
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Journal of Anthropological Research, 1987
Sites discovered by archaeological surveys are often recorded and interpreted in terms of site types. Problems with the taxon "limited activity site" are reviewed. Quantitative investigation of the nonassemblage characteristics (e.g., site size, artifact density, and artifact clustering) of thirty-four artifact scatters near Grasshopper Ruin in east ...
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Sites discovered by archaeological surveys are often recorded and interpreted in terms of site types. Problems with the taxon "limited activity site" are reviewed. Quantitative investigation of the nonassemblage characteristics (e.g., site size, artifact density, and artifact clustering) of thirty-four artifact scatters near Grasshopper Ruin in east ...
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A Surprising and Colorful Martian Scattering Artifact
Research Notes of the AAS, 2019Brittney Cooper, John Moores
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