No presente trabalho medimos e analisamos distribuições angulares para o processo de espalhamento elástico do núcleo radioativo de 12B em alvo de 58Ni. As medidas foram realizadas nas energias de Elab=30.0 e 33.0 MeV no laboratório do acelerador Pelletron. Essas energias são próximas a barreira Coulombiana (VB=28.0 MeV) para esse sistema. Para a produção do feixe radioativo de 12B utilizamos o sistema RIBRAS instalado nesse laboratório. As distribuições angulares foram analisadas com o modelo ótico, utilizando potenciais de Woods-Saxon e Potencial de São Paulo. Para uma interpretação física mais consistente e um estudo da influência de outros canais de reação no espalhamento elástico analisamos também considerando o método de canais acoplados. Considerando o acoplamento dos canais de espalhamento inelásticos, reorientação e spin-órbita pudemos descrever a distribuição angular na energia de 30.0 MeV. No entanto esses canais não foram suficientes para descrever a distribuição angular na energia de 33.0 MeV, indicando que outros canais como de transferência e/ou break-up possam ser importes. A partir da análise das distribuições angulares com modelo ótico obtivemos também a seção de choque total de reação. Essas seções de choque foram comparadas com a de outros sistemas utilizando métodos de redução, indicando que o projétil 12B segue uma sistemática intermediária entre núcleos fortemente ligados e fracamente ligados. Finalmente, discutimos a sistemática dos resultados de canais acoplados para o espalhamento elásticos dos isótopos de Boro 8,10,11,12B no alvo 58Ni em termos da configuração de clusters dos projéteis. / In the present work we measure and analyzed angular distributions for the process of elastic scattering of the radioactive nucleus of 12B in a target of 58Ni. The measurements were performed in the energies of Elab = 30.0 and 33.0 MeV in the Pelletron accelerator laboratory. These energies are close to the Colombian barrier (VB = 28.0 MeV) for this system. For the production of the radioactive beam of 12B we used the RIBRAS system installed in this laboratory. The angular distributions were analyzed with the optical model, using potentials of Woods-Saxon and Potential of São Paulo. For a more consistent physical interpretation and a study of the influence of other reaction channels in the elastic scattering we also analyze the coupled channel method. Considering the coupling of the inelastic scattering channels, reorientation and spin-orbit we could describe the angular distribution in the energy of 30.0 MeV. However, these channels were not enough to describe the angular distribution in the energy of 33.0 MeV, indicating that other channels as transfer and / or break-up can be amounts. From the analysis of the angular distributions with optical model we also obtained the section of total reaction shock. These cross sections were compared with those of other systems using reduction methods, indicating that projectile 12B follows a systematic intermediate between tightly bound and weakly bonded cores. Finally, we discuss the systematics of the results of elastic scattering channels of the Boron isotopes 8,10,11,12B in the 58Ni target in terms of the cluster configuration of the projectiles.

Esse trabalho consistiu na medida e análise de distribuições angulares do espalhamento elástico e inelástico para núcleos de massa A=10 em alvos de 58Ni e no desenvolvimento de novos feixes secundários radioativos para o sistema RIBRAS. As distribuições angulares do sistema 10B+58Ni foram medidas nas energias E(lab)= 19, 20, 21, 23, 24, 25 e 35 MeV, no laboratório Tandar na Argentina, enquanto a distribuição angular do sistema 10C+58Ni foi medida na energia E(lab)= 35.3 MeV, utilizando o sistema TWINSOL, da Universidade de Notre Dame, Estados Unidos. O formalismo de canais acoplados foi utilizado para estudar a influência da estrutura deformada do núcleo 10B e da estrutura Bruniana do núcleo 10C. Os resultados indicaram a importância desses efeitos, bem como a possível influência dos canais de transferências e breakup. / This work consisted in the analysis and measurement of angular distributions for elastic and inelastic scattering of mass A=10 projectiles in 58Ni target, as well as in the development of new secondaries radioactive ion beams for the RIBRAS system. Angular distributions for the 10B+58Ni system were measured at E(lab)= 19, 20, 21, 23, 24, 25 and 35 MeV, at Tandar Laboratory in Argentina, while an angular distribution at E(lab)= 35.3 MeV for the 10C+58Ni was measured at the University of Notre Dame, USA, using the Twinsol system. The coupled channel formalism was used to investigate the influence deformed structure of the 10B and Brunian structure for 10C nucleus. The results indicated the importance of these effect as well as the possible influence of transfer and breakup channels. In this work the development of 10C, 14C and 12B beams were investigated for future use in the RIBRAS system.

Innerhalb der handschriftlichen Überlieferung, die aus dem Mittelalter auf uns gekommen ist, gehören Palimpseste zu den Zeugnissen, die schon immer in besonderer Weise das Interesse auf sich gezogen und Phantasien beflügelt haben.

Esse trabalho consistiu na medida e análise de distribuições angulares do espalhamento elástico e inelástico para núcleos de massa A=10 em alvos de 58Ni e no desenvolvimento de novos feixes secundários radioativos para o sistema RIBRAS. As distribuições angulares do sistema 10B+58Ni foram medidas nas energias E(lab)= 19, 20, 21, 23, 24, 25 e 35 MeV, no laboratório Tandar na Argentina, enquanto a distribuição angular do sistema 10C+58Ni foi medida na energia E(lab)= 35.3 MeV, utilizando o sistema TWINSOL, da Universidade de Notre Dame, Estados Unidos. O formalismo de canais acoplados foi utilizado para estudar a influência da estrutura deformada do núcleo 10B e da estrutura Bruniana do núcleo 10C. Os resultados indicaram a importância desses efeitos, bem como a possível influência dos canais de transferências e breakup. / This work consisted in the analysis and measurement of angular distributions for elastic and inelastic scattering of mass A=10 projectiles in 58Ni target, as well as in the development of new secondaries radioactive ion beams for the RIBRAS system. Angular distributions for the 10B+58Ni system were measured at E(lab)= 19, 20, 21, 23, 24, 25 and 35 MeV, at Tandar Laboratory in Argentina, while an angular distribution at E(lab)= 35.3 MeV for the 10C+58Ni was measured at the University of Notre Dame, USA, using the Twinsol system. The coupled channel formalism was used to investigate the influence deformed structure of the 10B and Brunian structure for 10C nucleus. The results indicated the importance of these effect as well as the possible influence of transfer and breakup channels. In this work the development of 10C, 14C and 12B beams were investigated for future use in the RIBRAS system.

Foram determinadas de maneira absoluta seções de choque duplamente diferenciais de produção de bremsstrahlung, para elétrons com energia cinética de 20, 50, 75 e 100~keV, nos elementos C, Al, Ag, Te, Ta e Au, e nos ângulos de emissão dos fótons $35^{\\mathrm}$, $90^{\\mathrm}$ e $131^{\\mathrm}$. As medidas foram realizadas na linha de feixe de baixa energia do Acelerador Microtron, do Instituto de Física da Universidade de São Paulo, em um arranjo que contou com três detetores de Ge hiperpuro, dois planares e um coaxial. Os alvos finos foram confeccionados pela técnica de deposição física de vapores, enquanto suas espessuras foram caracterizadas a partir da espectrometria de retroespalhamento de Rutherford. Foi desenvolvido um modelo analítico para descrever a função reposta de detetores de Ge, que permitiu a deconvolução dos espectros de bremsstrahlung entre os 12~keV e o ponto de máxima transferência de energia, com uma resolução de 1~keV. As seções de choque obtidas apresentam uma incerteza relativa entre 3\\% e 5\\%, e foram comparadas com os cálculos teóricos que constituem o estado da arte na temática, e com os poucos dados experimentais encontrados na literatura. / Bremsstrahlung doubly dierential cross sections were absolutely determined for electrons with kinetic energies of 20, 50, 75 and 100 keV, in the elements C, Al, Ag, Te, Ta e Au, and the photon emission angles of 35o, 90o and 131o. The measurements were performed at the low energy beam line of the S~ao Paulo Microtron Accelerator, using three high purity Ge detectors: two planar and one coaxial. Thin targets were obtained by the Physical Vapor Deposition technique, and their thicknesses were characterized through Rutherford Backscattering Spectroscopy. An analytical model was developed to describe the response function of Ge detectors, which allowed to unfold the bremsstrahlung spectra between 12 keV and the maximum energy transfer point, with an energetic resolution of 1 keV. The obtained cross sections present relative uncertainties between 3% and 5%. These results were compared with the higher accurate theoretical calculations and also with the experimental reports found in literature.

Orientador: Hugo Enrique Hernadez Figueroa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-25T04:08:57Z (GMT). No. of bitstreams: 1 Baron_RafaelAntonio_M.pdf: 2527156 bytes, checksum: b044c223ca1a051a13e9264f599fe8c2 (MD5) Previous issue date: 2014 / Resumo: Atualmente está em fase de projeto o novo acelerador de elétrons do Laboratório Nacional de Luz Síncrotron (LNLS). Este acelerador de partículas, denominado Sirius, é constituído por diversos sistemas de instrumentação, sendo um deles de particular interesse para o diagnóstico de posição do feixe de elétrons estocado no acelerador. Este sistema, denominado monitor de posição de feixe, é constituído por sua vez por outros subsistemas, dentre os quais uma eletrônica de RF, dedicado a fazer processamento analógico de sinais de Rádio Frequência advindos de sensores que interagem eletromagneticamente com o feixe de elétrons. Esta eletrônica de RF deve condicionar o sinal, fornecendo ganho, filtragem, linearidade e estabilidade necessárias na faixa de operação de potências de entrada para que o sinal possa ser digitalizado. Este trabalho tem por objetivo descrever a respeito do desenvolvimento desta eletrônica, abarcando o projeto do circuito de RF de alta linearidade e alta estabilidade, implementação em placa de circuito impresso e testes em bancada e no acelerador de elétrons UVX, do LNLS / Abstract: The new electron accelerator of the Brazilian Synchrotron Light Laboratory (LNLS) is being designed to provide users with more brilliant photon beams. This particle accelerator, called Sirius, is composed of hundreds of instrumentation systems that are responsible for the machine operation. The Beam Position Monitor System is dedicated to monitor the position of the electron beam stored inside the vacuum chamber of the machine. It is composed by a subsystem called RF Front-End, dedicated to the analog processing of the beam signals that is originated by the interaction between the ultra-relativistic electromagnetic field of the electron beam and sensors specially designed for it. The RF Front-End electronics have been designed to provide filtering and gain with high linearity and stability along all the input power range. This work presents the design of the electronics, its implementation in printed-circuit board and tests results that have been performed in the laboratory and with a real beam signal / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

The TRIUMF view screen system encompases a set of devices which individually image, and produce measurements of, the transverse profile of an accelerated electron beam. A control system is an essential component of the overall diagnostic device. The system requirements were compiled from those produced by the TRIUMF laboratory and from those based on the needs of the individual diagnostic devices. Based on the requirements, a control system was designed and implemented with a combination of industrial electrical and mechanical hardware, and a variety of software components. One component of the image reconstruction algorithm was validated with experimental data; the accuracy and precision of beam profile measurements was evaluated through simulation studies. Although it was not possible to demonstrate the satisfaction of requirements relating to alignment, it was shown that all other requirements were satisfied. / Graduate / 0798 / 0752 / 0605

abstract: X-ray free electron lasers (XFELs) provide several orders of magnitude brighter x-rays than 3rd generation sources. However, the electron beamlines and undulator magnets required are on the scale of kilometers, costing billions of dollars with only a half dozen or so currently operating worldwide. One way to overcome these limitations is to prebunch the electron beam on the scale of the x-ray wavelength. In this paper one such scheme is discussed, which uses a nanopatterned grating called a dynamical beam stop. This uses diffraction from crystal planes of the etched portion of a grating to impart a transverse modulation which becomes a temporal modulation via an emittance exchange (EEX). To expand upon this topic, dynamical electron diffraction intensities for a 200 nm thick Si(001) unpatterned membrane are simulated via the multislice method and compared to experiment for various crystallographic orientations at MeV energies. From this as well as an analysis of the experimental inelastic plasmon diffuse scattering, it is determined that the optimal transverse modulation would be formed from a bright field image of the beam stop, with the nanopattern being etched all the way through the membrane. A model quantifying the quality of the modulation - the bunching factor - as a function of contrast and duty factor is formulated and the optimal modulation is determined analytically. A prototype beam stop is then imaged in a transmission electron microscope (TEM) at 200 KeV, with the measured bunching factor of 0.5 agreeing with the model and approaching a saturated XFEL. Using the angular spectrum method, it is determined that the spatial coherence of the MeV energy electron beam is insufficient for significant self-imaging to occur for gratings with pitches of hundreds of nanometers. Finally, the first-order EEX input requirements for the electron beam are examined in the transverse dimension as are newly proposed longitudinal requirements to compensate for lingering correlations between the initial and final longitudinal phase spaces. / Dissertation/Thesis / Doctoral Dissertation Physics 2020

This report explains how an SMES is operated and how SMES systems could be used to increase the efficiency of the CERN Large Hadron Collider (LHC) and the Future Circular Collider (FCC) as well as to reduce the very high power needs of a future Muon Collider (MC). The performance of SMES for other applications and late developments of the technique will also be described.

Particle accelerators are a leading tool for frontier science. Pushing that frontier further demands more machines with higher performance, and more of a very expensive technology: superconducting radio-frequency (SRF) acceleration. From a materials perspective this means reducing residual surface resistance or raising the operating temperature (currently ~2 K) of SRF cavities. Both are pursued by materials modification: nitrogen doping/infusion in the first instance and coating with Nb3Sn in the second. Materials characterization is key to achieving understanding and directing RandD. However, very little has been done. This present work aims to fill the knowledge gap and to provide needed, validated tools to the accelerator science community. In this connection, SIMS, XPS and EBSD have proven especially valuable and represent the majority of discussion in this dissertation. / Doctor of Philosophy / Particle accelerators are a powerful tool that helps us expand our knowledge of science and how the universe works. Pushing that knowledge further requires us to use more and more powerful particle accelerators. Particle accelerators are based on a very expensive technology: superconducting radio-frequency (SRF) cavities. These cavities are hollow tubes made from niobium and shaped in such a way as to cause electromagnetic waves to form. These waves are what are used to accelerate particles. The energy input and loss of energy as heat are massive resulting in millions of dollars a year in electric bills at particle accelerator facilities. In order to build bigger and more powerful particle accelerates they most be more efficient or they become prohibitively expensive. In this dissertation I look at several next generation materials used in building particle accelerators. In particular I describe and go into detail about how to characterize these materials. In other words, how we determine the materials properties and how those properties affect the performance.