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Ion-induced effects in GEM & GEM/MHSP gaseous photomultipliers for the UV and the visible spectral range

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 نشر من قبل Alexey Lyashenko
 تاريخ النشر 2005
  مجال البحث فيزياء
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We report on the progress in the study of cascaded GEM and GEM/MHSP gas avalanche photomultipliers operating at atmospheric pressure, with CsI and bialkali photocathodes. They have single-photon sensitivity, ns time resolution and good localization properties. We summarize operational aspects and results, with the highlight of a high-gain stable gated operation of a visible-light device. Of particular importance are the results of a recent ion-backflow reduction study in different cascaded multipliers, affecting the detectors stability and the photocathodes liftime. We report on the significant progress in ion-blocking and provide first results on bialkali-photocathode aging under gas multiplication.



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