25 research outputs found
Gas Gain Uniformity Tests performed on Multi Wire Proportional Chambers for the LHCb Muon System
We present the experimental setup and the results of the gas gain uniformity tests performed as part of the quality control of the multiwire proportional chambers produced at CERN for the LHCb Muon system. The test provides a relative gas gain measurement over the whole chamber sensitive area. It is based on the analysis of the pulse height spectrum obtained when the chamber is exposed to {a^241}Am radioactive source. Since the measurement is normalized to the peak of a precise pulse generator, the gain uniformity can also be evaluated among different gas gaps and different chambers
A fast voltage preamplifier for use with MWPCs
We report the development of a voltage preamplifier for use with ionizing particles detection. It has been designed to match the requirements of a test station for muon Multiwire Proportional Chambers (MWPC) of the LHCb experiment at CERN. Simulation results and bench test measurements are presented, which exhibit the main circuit features: gain close to 500, rise time below 20 ns, bandwidth exceeding 30 MHz, input noise lower than . Other results that demonstrate the applicability of the device in other contexts, specially with X-Ray imaging systems based on position sensitive detectors and proportional counters, are presented
Tomografias com detector de raios -X sensĂvel Ă posição
Aborda detectores de raios –X sensĂveis Ă posição que permitem medir o nĂşmero de fĂłtons e suas posições de incidĂŞncia. Utiliza os detectores em sistemas tomográficos computadorizados para realizar testes nĂŁo destrutivos de baixo custo em objetos de pequenas dimensões. Avalia o potencial dos detectores a partir de tomografias de objetos testes em diferentes condições. Calibra o sistema tomográfico e determina parâmetros de utilização para avaliação uantitativa da imagem atravĂ©s de tomografias em corpos de prova de materiais homogĂŞneos. Apresenta os resultados obtidos com um detector sensĂvel Ă posição unidimensional contendo gás ArgĂ´nio com 10% de metano Ă 2 atm, janela de carbono de 8cm de comprimento, 2 mm de largura e 272 µm de espressura