Improved lifetime of microchannel-plate PMTs

• DOI: 10.1016/j.nima.2014.04.005
• Publication Date: 2014-04-13T01:16:07Z
• Authors: A. Lehmann; A. Britting; W. Eyrich; F. Uhlig; R. Dzhygadlo; A. Gerhardt; K. Götzen; R. Höhler; G. Kalicy; H. Kumawat; D. Lehmann; B. Lewandowski; M. Patsyuk; K. Peters; G. Schepers; L. Schmitt; C. Schwarz; J. Schwiening; M. Traxler; M. Zühlsdorf; V.Kh. Dodokhov; M. Düren; K. Föhl; A. Hayrapetyan; B. Kröck; O. Merle; J. Rieke; E. Cowie; T. Keri; R. Montgomery; G. Rosner; P. Achenbach; M. Cardinali; M. Hoek; W. Lauth; C. Sfienti; M. Thiel; P. Bühler; L. Gruber; J. Marton; K. Suzuki
• Keywords: Microchannel plate detector; Particle identification; Quantum Efficiency

Abstract The charged particle identification at the PANDA experiment will be mainly performed with DIRC detectors. Because of their advantageous properties the preferred photon sensors are MCP-PMTs. However, until recently these devices showed serious aging problems which resulted in a diminishing quantum efficiency (QE) of the photo cathode. By applying innovative countermeasures against the aging causes, the manufacturers recently succeeded in drastically improving the lifetime of MCP-PMTs. Especially the application of an ALD coating technique to seal the material of the micro-channels proves very powerful and results in a lifetime of ≈ 6 C / cm 2 integrated anode charge without a substantial QE degradation for the latest PHOTONIS XP85112. This paper will present a comparative measurement of the lifetime of several older and recent MCP-PMTs demonstrating this progress.