Compton Scattering
Mostrando 1-12 de 12 artigos, teses e dissertações.
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1. Determination of the electron densities of breast neoplasias using the Compton scattering of X-rays / Determinação das densidades eletrônicas de neoplasias mamárias utilizando o espalhamento Compton de raios X
In this work we have been measured Compton scattering from normal and neoplastic (benign and malignant) in experiments using synchrotron radiation and X-rays tube, in order to determine of electronic densities of these tissues. The energies and scattering angles used were respectively 14,0 keV and 150º (x = 1,09 Å-1) for the measurements using synchrotron
Publicado em: 2008
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2. Espectroscopia de raios X utilizando o espalhamento Compton / X-ray spectroscopy using compton scattering
O estudo do espectro de raios X é importante para predizer a qualidade da imagem em sistemas radiográficos. Nesse trabalho usamos um detector semicondutor CdTe para medir os espectros de raios X na faixa de 25 a 120 kVp. Esse detector é pequeno e fácil de ser transportado. As medidas feitas diretamente do tubo de raios X não são aconselháveis devido �
Publicado em: 2008
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3. Deeply virtual compton scattering in color dipole formalism
In this contribution we summarize recent investigations on the deeply virtual Compton Scattering (DVCS) within the color dipole approach. The color dipole cross section is implemented through the phenomenological saturation model. The role played by its QCD evolution and skewedness effects in the DVCS cross section are discussed. The results are compared wit
Brazilian Journal of Physics. Publicado em: 2007-07
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4. Exclusive processes in diffraction at HERA
Recent results from the H1 and ZEUS experiments on exclusive processes in diffractive ep collisions at HERA are reviewed. The measurements discussed here include dijets and charm in photoproduction as well as in deep inelastic scattering. Such processes are sensitive to the partonic structure of the diffractive exchange, particularly to the gluon content, an
Braz. J. Phys.. Publicado em: 2007-06
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5. Metodologia para a obtenção da solução da equação de transporte de Botzmann considerando espalhamento Compton simulado por Klein-Nishina / Methodology for obtaining analytic solution for the boltzmann transport equation considering compton scattering simulated by klein-nishina
Nesse trabalho é apresentada uma solução analítica para a equação de transporte bidimensional em um domínio retangular considerando o espalhamento Compton, utilizando o método LTSN e a aproximação PN na variável angular. Esse procedimento leva a uma formulação para a taxa de dose total devido µa radiação gama. Nessa derivação, a energia dep
Publicado em: 2007
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6. "Espalhamento Compton e medida absoluta da energia de fótons marcados - Uma simulação Monte Carlo" / Compton scattering and absolute measurement of tagged photon energies.
A simulation based on Monte Carlo methods was created in order to evaluate the potentiality of using Compton scattering at high energies to obtain high precision absolute measurements of tagged photon energies. This method is based on angular measurements of the scattering products to reconstruct the incident photon energy using the kinematics of Compton sca
Publicado em: 2005
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7. The proton momentum distribution in water and ice
Deep Inelastic Neutron Scattering (Neutron Compton Scattering), is used to measure the momentum distribution of the protons in water from temperatures slightly below freezing to the supercritical phase. The momentum distribution is determined almost entirely by quantum localization effects, and hence is a sensitive probe of the local environment of the proto
Brazilian Journal of Physics. Publicado em: 2004-03
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8. Gamma-ray tracking with segmented HPGe detectors
This paper gives a brief overview of the technical progress that can be achieved with the newly available segmented HPGe detectors. Gamma-ray tracking detectors are a new generation of HPGe detectors which are currently being developed to improve significantly the efficiency and resolving power of the 4pi germanium detectors arrays for high-precision gamma-r
Brazilian Journal of Physics. Publicado em: 2003-06
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9. Coherent plasma processes in active galactic nuclei
The physics of active galactic nuclei (AGN) and related objects is one of the most actively pursued areas of astrophysics. Their large luminosities over the entire electromagnetic spectrum combined with extremely short time variability has stimulated a large number of astrophysicists to propose rather unconventional ideas. A variety of radiation mechanisms s
Brazilian Journal of Physics. Publicado em: 2002-12
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10. Quantitative Reconstruction of SPECT: Evaluation of Corrections / Reconstrução Quantitativa de SPECT: Avaliação de Correções
O objetivo deste trabalho foi avaliar a influência das correções de atenuação e espalhamento na reconstrução quantitativa em SPECT. O estudo foi baseado em diversas simulações de Monte Carlo, com ênfase especial no modelo torso-cardíaco matemático (MCAT). Para a reconstrução, foi utilizado o algoritmo iterativo ML-EM com projetor-retroprojetor
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 23/10/1998
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11. Geração de fotons muito duro por espalhamento Compton inverso da radiação sincrotron
The most efficient mechanism to generate photons in the 100 MeV energy range is by Inverse Compton scattering (ICS) of laser from relativistic electron. The energy of the emitted photons can be increased by raising either the energy of the electron, which is very expensive, or that of the photon. with the suggestion (S. Caticha-Ellis, 1983) that intense X-ra
Publicado em: 1993
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12. Source Theory Discussion of Deep Inelastic Scattering with Polarized Particles
A general phenomenological framework is provided for the discussion of the inelastic scattering of polarized electrons (muons) on polarized nucleons, when regarded as the absorption of polarized virtual photons. The relevant cross sections compare parallel and antiparallel orientations of the photon helicity and nucleon spin, and also deal with linear combin