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

A. Breskin·D. Mormann·A. Lyashenko·R. Chechik·F. D. Amaro·J. M. Maia·J. F. C. A. Veloso·J. M. F. dos Santos
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Abstract

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 detector's stability and the photocathode's 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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A. Breskin, D. Mormann, A. Lyashenko, R. Chechik, F. D. Amaro, J. M. Maia, J. F. C. A. Veloso, J. M. F. dos Santos. 2005-02-24. Ion-induced effects in GEM & GEM/MHSP gaseous photomultipliers for the UV and the visible spectral range. https://doi.org/10.1016/j.nima.2005.08.005

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