Difference between revisions of "PMT & Divider"

Revision as of 15:24, 4 May 2021

PMTs

• Hamamatsu R4125 PMT:

Specs

gain-HV

socket

Dynode location

Hamamatsu PMT manual

• Magnetic shielding

• TOSCA calculation (by Sasha Glamazdin)

presentation

(ppt file location /u/group/halld/Subsystems/HFCal/talk/Hybrid_FCal_shield.pptx)

Directory with TOSCA results /u/group/halld/Subsystems/HFCal/.

• Magnetic field measurements

Prototype of the PMT housing (magnetic field shielding)

• Procurement of PMTs in 2019

• PMT testing for Compton Calorimeter (2018)

PMT Active Base

• New Active PMT Base for PbWO4 (Popov, H. Mkrtchyan, presentation at IEEE, Nov 2012)

• Linearity measurements with CCAL

• Test performance of electronics using a 3x3 PWO prototype

• Active base performance at high rate

Modified Active Bases (2020)

• Test of modified active bases installed on CCAL (3 modules)

Three active bases were modified by V.Popov. They were installed and testes using the CCAL

• Estimates of the PMT Anode Current of the CCAL (FCAL2) Modules

• Schematic of the modified active base

(including resistor values for different amplifier gains)

• New modifications: (1) modify resistors to limit divider current below 1 mA (2) Increase voltages on first dynodes

- New bases installed in the Hall

Divider current after installation [1]

- Corresponding voltages

- Resistor values[2]

• Linearity test of the modified amplifier (gain 3)

• Latest design of the divider (April 2021, 900 uA at 1 kV)

Documents

PMT lifetime studies at FNAL