Navegação por Assunto "Perda de energia de particulas"
Resultados 1-20 de 46
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Alternative treatment for the energy-transfer and transport cross section in dressed electron-ion binary collisions
(2016) [Artigo de periódico]A formula for determining the electronic stopping power and the transport cross section in electron-ion binary collisions is derived from the induced density for spherically symmetric potentials using the partial-wave ... -
Análise de materiais nanoestruturados utilizando feixes de íons
(2009) [Tese]A miniaturização de dispositivos tecnológicos levou à percepção de novas classes de efeitos devidos ao con namento quântico e à mudança na proporção entre número de átomos presentes na superfície e no volume de estruturas ... -
Análise do efeito de proximidade e explosão coulombiana de íons moleculares em filmes ultrafinos
(2010) [Tese]Este trabalho tem como objetivo geral explorar os fenômenos decorrentes da interação de íons moleculares com a matéria, dando ênfase ao estudo dos efeitos de proximidade/ vizinhança e explosão colombiana para investigar ... -
Analytical energy loss distribution for accurate high resolution depth profiling using medium energy ion scattering
(2008) [Artigo de periódico]An analytical approach to ion energy loss distributions capable of simplifying medium energy ion scattering MEIS spectral analysis is presented. This analytical approach preserves the accuracy of recent numerical models ... -
Angle-dependent charge exchange and energy loss of slow highly charged ions in freestanding graphene
(2021) [Artigo de periódico]The scattering of ions in solids is accompanied with momentum transfer and electronic excitations resulting in the slowing down of the ion. The amount of energy transferred in a single scattering event depends on the ... -
Bohr's stopping-power formula derived for a classical free-electron gas
(2021) [Artigo de periódico]Bohr's centenary stopping-power formula is rederived for a free electron gas (FEG) system within the framework of nonrelativistic classical mechanics. A simple and more concise expression for the stopping power of charged ... -
Caracterização de nanoestruturas através da técnica MEIS
(2009) [Dissertação]Espalhamento de íons de energia intermediária (MEIS) é uma técnica analítica de feixe de íons que pode determinar quantitativamente composições elbmentares e perfis I de profundidade com resolução subnanométrica. Dessa ... -
Carbon deposition in Si as a consequence of H and He irradiations : a systematic study
(2002) [Artigo de periódico]In the present work we have investigated the influence of different parameters that determine the C deposition on a Si target. Among them we have studied the pressure of the irradiation chamber, the implantation fluence, ... -
Characterization of nanoparticles through medium-energy ion scattering
(2009) [Artigo de periódico]In this work we review the use of the medium-energy ion scattering (MEIS) technique to characterize nanostructures at the surface of a substrate. We discuss here how the determination of shape and size distribution of the ... -
Competing influence of damage buildup and lattice vibrations on ion range profiles in Si
(2003) [Artigo de periódico]Phosphorus depth profiles in Si obtained by 140 keV implantation in the [001] axial channel direction and in a direction 7° off axis are investigated at two different doses (531013 and 5 31015 cm22) for implantation ... -
Contribution of close collisions to the Barkas effect : the classical picture
(2004) [Artigo de periódico]According to a previous estimation made by Lindhard [Nucl. Instrum. Method Phys. Res. 132, 1 (1976)] on the basis of qualitative arguments and dimensional analysis, the contribution of close collisions to the Barkas effect ... -
Copper gettering at half the projected ion range induced by low-energy channeling He implantation into silicon
(2000) [Artigo de periódico]He1 ions were implanted at 40 keV into Si <100> channel direction at room temperature (RT) and at 350 °C. The Si samples were subsequently doped with Cu in order to study the gettering of Cu atoms at the defective layer. ... -
Coulomb heating of channeled C+ and C2+ molecules in Si
(2008) [Artigo de periódico]Si x-ray and backscattering yields have been measured as a function of the C⁺ and C₂⁺ entrance angle along the Si ‹100› channel in an energy interval between 900 and 2200 keV/atom. A significant enhancement of the x-ray ... -
Direct observation and theory of trajectory-dependent electronic energy losses in medium-energy ion scattering
(2009) [Artigo de periódico]The energy spectrum associated with scattering of 100 keV H⁺ ions from the outermost few atomic layers of Cu(111) in different scattering geometries provides direct evidence of trajectory-dependent electronic energy loss. ... -
Efeitos de espalhamentos múltiplos na análise de materiais nanoestruturados via MEIS
(2013) [Dissertação]A síntese de sistemas nanoestruturados bidimensionais enterrados em matrizes sólidas têm atraído interesse em associação, por exemplo, com aplicações plasmônicas e magnéticas. Para ambas, as propriedades dos sistemas de ... -
Electronic energy loss of channeled ions : the giant Barkas effect
(2004) [Artigo de periódico]In this work we have measured the electronic energy loss of ⁹Be and ¹¹B ions for the ‹100› and ‹110› directions in Si as a function of the incident ion energy. The channeling measurements cover a wide energy range between ... -
Energy deposition of H and He ion beams in hydroxyapatite films : a study with implications for ion-beam cancer therapy
(2014) [Artigo de periódico]Ion-beam cancer therapy is a promising technique to treat deep-seated tumors; however, for an accurate treatment planning, the energy deposition by the ions must be well known both in soft and hard human tissues. Although ... -
Energy loss in medium-energy ion scattering : a combined theoretical and experimental study of the model system Y on Si(111)
(2005) [Artigo de periódico]The energy-loss spectrum associated with scattering of 100 keV H+ ions from Y atoms on Si (111) has been investigated both experimentally and theoretically. Measurements were made from Y overlayers, and from the Si (111) ... -
Energy loss of helium ions in zinc
(2004) [Artigo de periódico]The energy loss of helium ions in zinc has been measured in the energy range from 37.5 to 1750 keV/amu using the transmission technique and the Rutherford backscattering method. In addition, calculations using the extended ... -
Energy loss of proton, [alpha] particle, and electron beams in hafnium dioxide films
(2009) [Artigo de periódico]The electronic stopping power, S, of HfO₂ films for proton and alpha particle beams has been measured and calculated. The experimental data have been obtained by the Rutherford backscattering technique and cover the range ...
