MARGARIDA R. F. FRAGA

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Agora exibindo 1 - 4 de 4
  • Artigo IPEN-doc 22602
    Rate effects in radiation detectors with resistive electrodes
    1998 - FRAGA, M.M.; LIMA, E.P. de; MARQUES, R.F.; POLICARPO, A.J.P.L.; BUENO, CARMEN C.; GONÇALVES, JOSEMARY A.C.; SANTOS, M.D. de S.
    Detectors with highly resistive electrodes, particularly RPCs, have been studied extensively in recent years. Several authors considered the effect of rate on the detector response (efficiency) and a few also associated with the rate, in a rather qualitative manner, the charge per event, i.e., the current. Here, without loss of generality of the results obtained, rate effects are studied with a classical cylindrical counter geometry and different gas mixtures. To a high accuracy, the observed behavior, both for the proportional mode and for the transition to streamers, is quantitatively and accurately interpreted as loss of voltage on the dielectric due to the current generated in the detector, with direct consequences for the local electric field in the avalanche region. Results obtained in the self quenching streamer (SQS) mode fail the previous interpretation and clearly need further research.
  • Artigo IPEN-doc 12833
    Rad-Hard silicon diode response for photon spectrometry
    2007 - GONCALVES, J.A.C.; CAMARGO, F.; FRAGA, M.M.R.; PINTO, J.K.C.; BUENO, C.C.
  • Artigo IPEN-doc 08242
    Pressure dependence of secondary NIR scintillation in Ar and Ar/CFsub(4)
    2001 - FRAGA, M.M.; BUENO, C.C.; GONCALVES, J.A.C.; FRAGA, F.A.F.; FERREIRA MARQUES, R.; POLICARPO, A.J.P.L.
  • Artigo IPEN-doc 07373
    Study of scintillation light from microstructure based detectors
    2000 - FRAGA, M.M.; FETAL, S.T.G.; FRAGA, F.A.F.; ANTUNES, E.; GONCALVES, J.A.C.; BUENO, C.C.; FERREIRA MARQUES, R.; POLICARPO, A.J.P.L.