The muon lifetime experiment
PART II: Scintillator conditioning and PMT mounting

Fixing & polishing. This scintillator cracked because of out of control temperature. However it was still useful as it cracked exactly through its diameter.

Painted with styrene (monomer) with a soft brush. Surface recovers brightness. Dry well.

Monomer deposit on concave bottom. Polymerizes well in two or three days. Provides a flat surface where to fix the 2" PMT. Can be heated with a lamp.

Heavy duty aluminium foil. Not painted with white latex (see ref) as distances are relatively short.

First aluminiun wrapping.

Photonis XP2020Q PMT whith magnetic shield isolated with black rubber in order to be feed with negative high voltage power supply.

PMT stick with vacuum grease. Fixes well but does not support its own weight. Do not hang.

Neck of the first aluminium wrapping.

Sealed with black tape.

A black rubber wrapping and finally a second loose aluminium foil.

PMT Socket.

Manufacturer recommended Voltage Divider
Type A for maximum gain
K G D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 A
1.2 2.8 1.2 1.8 1 1 1 1 1 1 1 1 1 1
(total: 17)

Polyvinyl Acetate (PVA)
Refractive index 1.45