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Statistical treatment of misalignments in particle accelerators

Silva, Tiago Fiorini da; Martins, Marcos Nogueira
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.01%
To know how much misalignment is tolerable for a particle accelerator is an important input for the design of these machines. In particle accelerators the beam must be guided and focused using bending magnets and magnetic lenses, respectively. The alignment of the lenses along a transport line aims to ensure that the beam passes through their optical axes and represents a critical point in the assembly of the machine. There are more and more accelerators in the world, many of which are very small machines. Because the existing literature and programs are mostly targeted for large machines. in this work we describe a method suitable for small machines. This method consists in determining statistically the alignment tolerance in a set of lenses. Differently from the methods used in standard simulation codes for particle accelerators, the statistical method we propose makes it possible to evaluate particle losses as a function of the alignment accuracy of the optical elements in a transport line. Results for 100 key electrons, on the 3.5-m long conforming beam stage of the IFUSP Microtron are presented as an example of use. (C) 2010 Elsevier B.V. All rights reserved.; FAPESP; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); CNPq; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Implantação de um programa de controle de qualidade para sistemas de planejamento de tratamento computadorizados de acordo com o TRS 430; Implementation of a quality assurance program for computerized treatment planning systems according to TRS 430

Camargo, Priscilla Roberta Tavares Leite
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/04/2006 Português
Relevância na Pesquisa
26.86%
No presente trabalho serão apresentadas as diretrizes e os testes necessários para a implantação de um programa de controle de qualidade para o Eclipse 7.3.10 da Varian no Hospital das Clínicas da Faculdade de Medicina da USP, de acordo com a mais recente publicação da AIEA o TRS 430. Os testes recomendados pelo TRS 430 são basicamente divididos em testes de aceitação, comissionamento (testes dosimétricos e não dosimétricos), e testes rotineiros. O documento da AIEA está sendo implementado para o Eclipse no HC para os feixes de fótons de dois aceleradores lineares da Varian, Clinac 600C e Clinac 2100C. Os testes de aceitação verificaram parâmetros de "hardware"; integração do sistema "network"; transferência de dados, e "softwares". Os resultados obtidos mostraram boa concordância com as especificações do fabricante. Para os testes dosimétricos de comissionamento, foram realizadas medidas de dose absoluta para diversos arranjos experimentais. Esses valores foram comparados com os valores de dose gerados pelo SPTC. A grande maioria dos testes apresentou cerca de 90% a 80% dos pontos comparados, dentro dos níveis de tolerância, ou seja, uma boa concordância entre os valores experimentais e os valores gerados pelo SPTC. Somente arranjos de campos assimétricos apresentaram discordâncias grosseiras...

Projeto, construção e caracterização de sistemas de referência para feixes de elétrons de aceleradores clínicos; Design, construction and characterization of reference systems for electron beams of clinical accelerators

Nonato, Fernanda Beatrice Conceição
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 23/10/2014 Português
Relevância na Pesquisa
37.23%
Os aceleradores lineares vêm substituindo gradativamente os irradiadores de fontes gama nos Serviços de Radioterapia no Brasil. Consequentemente, existe a necessidade de aquisição de câmaras de ionização para uso em dosimetria dos feixes de radiação X e de elétrons dos aceleradores lineares. Entretanto, as câmaras de ionização comerciais para radioterapia apresentam alto custo e todas são importadas. Este trabalho teve como objetivo principal projetar, construir e caracterizar câmaras de ionização de placas paralelas em dosimetria de feixes de elétrons de aceleradores clínicos. Foram desenvolvidas cinco câmaras de ionização utilizando-se acrílico como material principal e tintas de grafite e de prata para a confecção dos eletrodos coletores. Uma das câmaras de ionização é a prova dágua. Todas as câmaras de ionização foram submetidas a feixes de radiação no Laboratório de Calibração de Instrumentos do IPEN e em três Serviços de Radioterapia na cidade de São Paulo onde foram realizados testes, como: tempo de estabilização, repetibilidade da resposta, estabilidade a médio prazo, corrente de fuga, corrente de saturação, eficiência de coleção de íons, linearidade de resposta, variação da resposta com a distância fonte-detector...

A runtime system for data-flow task programming on multicore architectures with accelerators; Uma ferramenta para programação com dependência de dados em arquiteturas multicore com aceleradores; Vers un support exécutif avec dépendance de données pour les architectures multicoeur avec des accélérateurs

Lima, João Vicente Ferreira
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
37.01%
In this thesis, we propose to study the issues of task parallelism with data dependencies on multicore architectures with accelerators. We target those architectures with the XKaapi runtime system developed by the MOAIS team (INRIA Rhône-Alpes). We first studied the issues on multi-GPU architectures for asynchronous execution and scheduling. Work stealing with heuristics showed significant performance results, but did not consider the computing power of different resources. Next, we designed a scheduling framework and a performance model to support scheduling strategies over XKaapi runtime. Finally, we performed experimental evaluations over the Intel Xeon Phi coprocessor in native execution. Our conclusion is twofold. First we concluded that data-flow task programming can be efficient on accelerators, which may be GPUs or Intel Xeon Phi coprocessors. Second, the runtime support of different scheduling strategies is essential. Cost models provide significant performance results over very regular computations, while work stealing can react to imbalances at runtime.; Esta tese investiga os desafios no uso de paralelismo de tarefas com dependências de dados em arquiteturas multi-CPU com aceleradores. Para tanto, o XKaapi, desenvolvido no grupo de pesquisa MOAIS (INRIA Rhône-Alpes)...

Dessorção de gases de juntas soldadas em camaras de ultra-alto vacuo de aneis de armazanamento de eletrons; Gas desorption from welded joints on electron storage rings ultrahigh vacuum systems

Rafael Molena Seraphim
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/02/2007 Português
Relevância na Pesquisa
27.11%
O avanço cientifico no estudo de átomos, moléculas e proteínas tem recebido uma contribuição significativa dos aceleradores de partículas, que em sua grande maioria são utilizados para a geração de radiação síncrotron. Por isso, o aprimoramento destas máquinas mostra-se de extrema importância para manter a ciência em seu contínuo avanço. O sistema de vácuo destas máquinas apresenta-se como um importante parâmetro para o seu bom funcionamento e melhorias neste promovem diretamente melhorias na qualidade da radiação síncrotron gerada. Logo, o desenvolvimento deste trabalho teve como principal objetivo o estudo das juntas soldadas das câmaras de vácuo que compõem o acelerador do Laboratório Nacional de Luz Síncrotron (LNLS). As juntas foram preparadas com o processo de soldagem GTAW (Gás Tungsten Arc Welding) mediante a utilização de diferentes gases de proteção, como Argônio, Hélio e Nitrogênio, e misturas entre estes. Os estudos concentraram-se na análise da influência dos gases de proteção na dessorção de gases das juntas soldadas. Para a caracterização destas utilizaram-se as técnicas de análise de superfícies Dessorção Estimulada por Elétrons (DEE) e Dessorção Estimulada por Fótons (DEF). Adicionalmente...

THE ACTION OF SOME HEMOLYSIS ACCELERATORS UPON LIPID AND PROTEIN MONOLAYERS

Chen, Helen L.; Collier, H. B.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 20/09/1951 Português
Relevância na Pesquisa
26.86%
The effect of three accelerators of hemolysis—acetylphenylhydrazine, 9-aminoacridine, and phenothiazone—upon protein and lipid monolayers has been examined. These compounds, in low concentration, cause marked expansion of monolayers of plasma albumin, but have no apparent effect upon cholesterol films. It is suggested that these accelerators may affect the protein component of the erythrocyte membrane, thus enhancing the action of hemolytic agents.

Evaluation methods for detecting changes in beam output and energy in radiation beams from high-energy linear accelerators

Ravichandran, R.; Binukumar, J. P.; Davis, C. A.; Krishnamurthy, K.; Sivakumar, S. S.
Fonte: Medknow Publications Publicador: Medknow Publications
Tipo: Artigo de Revista Científica
Publicado em //2007 Português
Relevância na Pesquisa
26.86%
There is need for simple methods for checking consistency of beam outputs and energy in linear accelerators used for radiotherapy. A method was designed by the department using perspex phantom with which the dosimetric data of two medical linear accelerators (Clinac 600 CD, Clinac 2300 CD) were evaluated over a period of 30 months. The efficacy of methods followed was checked. Routine beam consistency checks were designed for photon beams with 15 cm/ 5 cm depth ionizations in perspex phantom and variable depth combinations for electron beams. Calculated ionization ratios were compared with measured values to show their significance. The dose/MU for all radiation beams was maintained within 2% accuracy over the period of 30 months. Clinac 600 CD machine showed decreasing trend of cGy/MU, while Clinac 2300 CD showed increasing trend of cGy/MU over a period, which needed tuning of monitor chamber two times each. Tuning of output to achieve standard value was carried out once, for all electron energies when the output dose/MU exceeded 3%. During one week (June 2005), there were slight changes in electron energy detected using the ratio method, which did not recur anytime afterwards. The methods designed are adequate to find the consistency in the beam output and energies in the radiotherapy linacs.

Fast Acceleration of 2D Wave Propagation Simulations Using Modern Computational Accelerators

Wang, Wei; Xu, Lifan; Cavazos, John; Huang, Howie H.; Kay, Matthew
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 30/01/2014 Português
Relevância na Pesquisa
27.01%
Recent developments in modern computational accelerators like Graphics Processing Units (GPUs) and coprocessors provide great opportunities for making scientific applications run faster than ever before. However, efficient parallelization of scientific code using new programming tools like CUDA requires a high level of expertise that is not available to many scientists. This, plus the fact that parallelized code is usually not portable to different architectures, creates major challenges for exploiting the full capabilities of modern computational accelerators. In this work, we sought to overcome these challenges by studying how to achieve both automated parallelization using OpenACC and enhanced portability using OpenCL. We applied our parallelization schemes using GPUs as well as Intel Many Integrated Core (MIC) coprocessor to reduce the run time of wave propagation simulations. We used a well-established 2D cardiac action potential model as a specific case-study. To the best of our knowledge, we are the first to study auto-parallelization of 2D cardiac wave propagation simulations using OpenACC. Our results identify several approaches that provide substantial speedups. The OpenACC-generated GPU code achieved more than speedup above the sequential implementation and required the addition of only a few OpenACC pragmas to the code. An OpenCL implementation provided speedups on GPUs of at least faster than the sequential implementation and faster than a parallelized OpenMP implementation. An implementation of OpenMP on Intel MIC coprocessor provided speedups of with only a few code changes to the sequential implementation. We highlight that OpenACC provides an automatic...

An Electrostatic Type Electron Diffraction Unit with Intermediate Electron Accelerators

SAITO, Kazuo
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
Português
Relevância na Pesquisa
27.01%
A new experimental electrostatic type electron optical instrument, which works as a 150kV electron diffraction unit, a 150kV shadow electron microscope and a 100kV electron microscope, is described. The instrument has two intermediate electron accelerators to which positive high potentials are supplied. One of the accelerators is located before the objective lens and used for the electron microscopy, and the other is after the projector lens and used for the electron diffraction or the shadow electron microscopy. The constructions of the column and the high voltage power unit are simplified by using the intermediate accelerators. Some typical results obtained with the instrument are also reported.

Application-Specific Accelerators for Communications

Sun, Yang; Amiri, Kiarash; Brogioli, Michael; Cavallaro, Joseph R.
Fonte: Springer Science+Business Media, LLC Publicador: Springer Science+Business Media, LLC
Tipo: Parte de Livro
Português
Relevância na Pesquisa
27.01%
For computation-intensive digital signal processing algorithms, complexity is exceeding the processing capabilities of general-purpose digital signal processors (DSPs). In some of these applications, DSP hardware accelerators have been widely used to off-load a variety of algorithms from the main DSP host, including FFT, FIR/IIR filters, multiple-input multiple-output (MIMO) detectors, and error correction codes (Viterbi, Turbo, LDPC) decoders. Given power and cost considerations, simply implementing these computationally complex parallel algorithms with high-speed general-purpose DSP processor is not very efficient. However, not all DSP algorithms are appropriate for off-loading to a hardware accelerator. First, these algorithms should have data-parallel computations and repeated operations that are amenable to hardware implementation. Second, these algorithms should have a deterministic dataflow graph that maps to parallel datapaths. The accelerators that we consider are mostly coarse grain to better deal with streaming data transfer for achieving both high performance and low power. In this chapter, we focus on some of the basic and advanced digital signal processing algorithms for communications and cover major examples of DSP accelerators for communications.

A implantação da ciência de base tecnológica : um estudo do desenvolvimento da física experimental com aceleradores de partículas na Universidade de São Paulo (1934-1982); The introduction of the technology-based science : a study of the development of experimental physics with particle accelerators in the University of São Paulo (1934-1982)

Tharsila Reis de Medeiros
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 03/12/2012 Português
Relevância na Pesquisa
37.11%
O tema central do presente trabalho reside no desenvolvimento da física experimental com aceleradores de partículas na Universidade de São Paulo (USP), mais especificamente nos empreendimentos científicos do físico Oscar Sala. O ponto de partida da narrativa aqui proposta se encontra em 1934, ano em que a atividade de investigação científica do recém criado Departamento de Física da USP deu seus primeiros passos em direção à Física dos Raios Cósmicos, sendo este seu principal ramo de pesquisa experimental nos próximos dez anos. Argumenta-se que esse período foi de fundamental importância à posterior inserção da USP na era dos aceleradores de partículas, devido à continuidade instrumental verificada entre a Física Nuclear e a dos Raios Cósmicos. Foi nesse último ramo que Oscar Sala realizou sua iniciação científica, começando, logo após a Segunda Guerra Mundial, seu primeiro empreendimento científico - projetar e construir, na sua própria universidade e com a colaboração de empresas instaladas em São Paulo, um acelerador de partículas do tipo Van de Graaff. Constata-se que a consolidação do Laboratório do Acelerador Eletrostático se tornou possível graças à filantropia científica norte americano e à cooperação científica firmada com o Departamento de Física Nuclear da Universidade de Wisconsin. Em meados dos anos 1960...

Dosimetric analysis of beam-matching procedure of two similar linear accelerators

Bhangle, Janhavi R.; Narayanan, V. K. Sathiya; Kumar, Namitha K.; Vaitheeswaran, R.
Fonte: Medknow Publications Pvt Ltd Publicador: Medknow Publications Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
27.11%
Linear accelerators from the same vendor in a radiation therapy center are usually beam-matched following Vendor's acceptance criteria. This protocol is limited to check the difference at particular points on the ionization curve for depth dose or beam profiles. This article describes different tests done after commissioning to evaluate the level of agreement between matched beams of two ONCOR Impression plus linear accelerators from Siemens. Total scatter factors, collimator scatter factors, wedge transmission factors were measured in water for 6-MV photon. All these factors for ONCOR2 were within ±1% of those values for ONCOR1. Along with these point dose measurements we have essentially used γ-index to compare the planar dose distribution from two beam-matched accelerators. For this study a set of ready packed EDR2 films was exposed on both accelerators. The set consisted of films for percentage depth dose, beam profiles, a pyramid shape, multileaf collimator's positional and dose delivery accuracy, and a film to compare head scatter at tray level. To include treatment planning system calculations, a film kept in axial plane was exposed to 3DCRT and IMRT plans with actual gantry angles and monitor units. These films were analyzed for γ in OmniPro IMRT software using different combinations of Δdose and - Δdistances. All these films have shown good agreement for - Δdistance of 3 mm and Δdose of 3 %.

Hydrostatic Level Sensors as High Precision Ground Motion Instrumentation for Tevatron and Other Energy Frontier Accelerators

Volk, J.; Hansen, S.; Johnson, T.; Jostlein, H.; Kiper, T.; Shiltsev, V.; Chupyra, A.; Kondaurov, M.; Medvedko, A.; Parkhomchuk, V.; Singatulin, S.; Stetler, L.; Van Beek, J.; Fratta, D.; Roberts, J.; Wang, H.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/05/2012 Português
Relevância na Pesquisa
27.11%
Particle accelerators pushed the limits of our knowledge in search of the answers to most fundamental questions about micro-world and our Universe. In these pursuits, accelerators progressed to higher and higher energies and particle beam intensities as well as increasingly smaller and smaller beam sizes. As the result, modern existing and planned energy frontier accelerators demand very tight tolerances on alignment and stability of their elements: magnets, accelerating cavities, vacuum chambers, etc. In this article we describe the instruments developed for and used in such accelerators as Fermilab's Tevatron (FNAL, Batavia, IL USA) and for the studies toward an International Linear Collider (ILC). The instrumentation includes Hydrostatic Level Sensors (HLS) for very low frequency measurements. We present design features of the sensors, outline their technical parameters, describe test and calibration procedures and discuss different regimes of operation. Experimental results of the ground motion measurements with these detectors will be presented in subsequent paper.

Study of quality assurance regulations for linear accelerators in Korea: A comparison study between the current status in Korea and the international guidelines

Lee, Hyunho; Jeong, Seonghoon; Jo, Yunhui; Yoon, Myonggeun
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/03/2015 Português
Relevância na Pesquisa
27.23%
Quality assurance (QA) for medical linear accelerators is indispensable for appropriate cancer treatment. Some international organizations and western advanced countries provide QA guidelines for linear accelerators. Currently, QA regulations for linear accelerators in Korean hospitals specify a system in which each hospital stipulates its independent hospital-based protocols for QA procedures (HP_QAPs) and conducts QA based on these HP_QAPs while regulatory authorities verify whether items under these HP_QAPs have been performed. However, because this regulatory method cannot guarantee the quality of universal treatment, and QA items with tolerance criteria are different in many hospitals, the presentation of standardized QA items and tolerance criteria is essential. In this study, QA items in HP_QAPs from various hospitals and those presented by international organizations. Concordance rates between QA items for linear accelerators that were presented by the aforementioned organizations and those currently being implemented in Korean hospitals were shown to exhibit a daily QA of 50%, a weekly QA of 22%, a monthly QA of 43%, and an annual QA of 65%, and the overall concordance rates of all QA items were approximately 48%. In comparison between QA items being implemented in Korean hospitals and those being implemented in western advanced countries...

Physics Needs for Future Accelerators

Lykken, Joseph D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/01/2000 Português
Relevância na Pesquisa
27.11%
Contents: 1. Prologomena to any meta future physics 1.1 Physics needs for building future accelerators 1.2 Physics needs for funding future accelerators 2. Physics questions for future accelerators 2.1 Crimes and misapprehensions 2.1.1 Organized religion 2.1.2 Feudalism 2.1.3 Trotsky was right 2.2 The Standard Model as an effective field theory 2.3 What is the scale of new physics? 2.4 What could be out there? 2.5 Model-independent conclusions 3. Future accelerators 3.1 What is the physics driving the LHC? 3.2 What is the physics driving the LC? 3.2.1 Higgs physics is golden 3.2.2 LHC won't be sufficient to unravel the new physics as the TeV scale 3.2.3 LC precision measurements can pin down new physics scales 3.3 Why a Neutrino Factory? 3.4 Pushing the energy frontier; Comment: 19 pages, 7 figures. Talk presented at the XIX International Symposium on Lepton and Photon Interactions at High Energies (Lepton-Photon '99), Stanford University, August 9-14, 1999

Developments in laser-driven plasma accelerators

Hooker, Simon Martin
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/06/2014 Português
Relevância na Pesquisa
27.11%
Laser-driven plasma accelerators provide acceleration gradients three orders of magnitude greater than conventional machines, offering the potential to shrink the length of accelerators by the same factor. To date, laser-acceleration of electron beams to particle energies comparable to those offered by synchrotron light sources has been demonstrated with plasma acceleration stages only a few centimetres long. This article describes the principles of operation of laser-driven plasma accelerators, and reviews their development from their proposal in 1979 to recent demonstrations. The potential applications of plasma accelerators are described and the challenges which must be overcome before they can become a practical tool are discussed.

Multi-Pulse Laser Wakefield Acceleration: A New Route to Efficient, High-Repetition-Rate Plasma Accelerators and High Flux Radiation Sources

Hooker, S. M.; Bartolini, R.; Mangles, S. P. D.; Tünnermann, A.; Corner, L.; Limpert, J.; Seryi, A.; Walczak, R.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/01/2014 Português
Relevância na Pesquisa
27.11%
Laser-driven plasma accelerators can generate accelerating gradients three orders of magnitude larger than radio-frequency accelerators and have achieved beam energies above 1 GeV in centimetre long stages. However, the pulse repetition rate and wall-plug efficiency of plasma accelerators is limited by the driving laser to less than approximately 1 Hz and 0.1% respectively. Here we investigate the prospects for exciting the plasma wave with trains of low-energy laser pulses rather than a single high-energy pulse. Resonantly exciting the wakefield in this way would enable the use of different technologies, such as fibre or thin-disc lasers, which are able to operate at multi-kilohertz pulse repetition rates and with wall-plug efficiencies two orders of magnitude higher than current laser systems. We outline the parameters of efficient, GeV-scale, 10-kHz plasma accelerators and show that they could drive compact X-ray sources with average photon fluxes comparable to those of third-generation light source but with significantly improved temporal resolution. Likewise FEL operation could be driven with comparable peak power but with significantly larger repetition rates than extant FELs.

Ion sources for high-power hadron accelerators

Faircloth, Dan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/02/2013 Português
Relevância na Pesquisa
27.11%
Ion sources are a critical component of all particle accelerators. They create the initial beam that is accelerated by the rest of the machine. This paper will introduce the many methods of creating a beam for high-power hadron accelerators. A brief introduction to some of the relevant concepts of plasma physics and beam formation is given. The different types of ion source used in accelerators today are examined. Positive ion sources for producing H+ ions and multiply charged heavy ions are covered. The physical principles involved with negative ion production are outlined and different types of negative ion sources are described. Cutting edge ion source technology and the techniques used to develop sources for the next generation of accelerators are discussed.; Comment: Presented at the CERN Accelerator School CAS 2011: High Power Hadron Machines, Bilbao, 24 May - 2 June 2011

Future HEP Accelerators: The US Perspective

Bhat, Pushpalatha; Shiltsev, Vladimir
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/11/2015 Português
Relevância na Pesquisa
27.01%
Accelerator technology has advanced tremendously since the introduction of accelerators in the 1930s, and particle accelerators have become indispensable instruments in high energy physics (HEP) research to probe Nature at smaller and smaller distances. At present, accelerator facilities can be classified into Energy Frontier colliders that enable direct discoveries and studies of high mass scale particles and Intensity Frontier accelerators for exploration of extremely rare processes, usually at relatively low energies. The near term strategies of the global energy frontier particle physics community are centered on fully exploiting the physics potential of the Large Hadron Collider (LHC) at CERN through its high-luminosity upgrade (HL-LHC), while the intensity frontier HEP research is focused on studies of neutrinos at the MW-scale beam power accelerator facilities, such as Fermilab Main Injector with the planned PIP-II SRF linac project. A number of next generation accelerator facilities have been proposed and are currently under consideration for the medium- and long-term future programs of accelerator-based HEP research. In this paper, we briefly review the post-LHC energy frontier options, both for lepton and hadron colliders in various regions of the world...

Linear accelerators

Vretenar, Maurizio
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/03/2013 Português
Relevância na Pesquisa
27.01%
Radio-frequency linear accelerators are used as injectors for synchrotrons and as stand-alone accelerators for the production of intense particle beams, thanks to their ability to accelerate high beam currents at high repetition rates. This lecture introduces their main features, reviewing the different types of accelerating structures used in linacs and presenting the main characteristics of linac beam dynamics. Building on these bases, the architecture of modern proton linear accelerators is presented with a particular emphasis on high-energy and high-beam-power applications.; Comment: 25 pages, contribution to the CAS - CERN Accelerator School: Course on High Power Hadron Machines; 24 May - 2 Jun 2011, Bilbao, Spain