TPB evaporation Maura Spanu, Università di Pavia, INFN Pavia WA-104 weekly meeting 24/02/2016

Evaporation status 2 Last week we had some problems with crucible 2 (probably due to the temperature gauge). This week the series production is ongoin but only with the crucible 1. For the C2 we must draft a new coating procedure (temperature steps).

Knudsen cell calibration 3 1.Do an open evaporation: Temperature VS Rate 2.Fix a rate value which corresponds to the shutter opening temperature (the rate depends on the distance from the quartz crystal) 3.Test your evaporation with the mockup: - Average Rate in stable condition (for C2) ≈ Time < 15:00 - Final thickness > 5,0 Å Last week we had some problems with crucible 2 (probably due to the temperature gauge). This week the series production is ongoin but only with the crucible 1. For the C2 we must draft a new coating procedure (temperature steps).

QE measurements 4 The last week, a QE test will be done in Pavia on 5 evaporated PMTs.

QE results 5

Conclusions PMT’s are now evaporated and stocked in B182 (other 18 PMTs are cleaned and ready to be evaporated).  7-> to be cleaned and redone (density < 0,19 mg/cm 2 )  5 -> to be checked  1 -> already checked, seems good At: 7: :subDocs you can find the updated evaporation database.