Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Photomultiplier
Date: Oct 02, 7:23 pm
Poster: Richard Hester

On Oct 02, 7:23 pm, Richard Hester wrote:

PMTS with no voltage on them will not be damaged by incident light short of a laser beam or vortex lamp. However, with voltage applied, normal room illumination will zorch the more sensitive types (read large number of dynodes).
In a detector, the PMT and scintillator are optically coupled (silicone grease works) and sealed in a light tight enclosure of some sort. This could be a crude as a cardboard tube wrapped with black electrical tape or as sophisticated as a mu-metal shielded enclosure.

OE tech sells some PMT housings, but they are not too cheap.

Richard Hester



>Hi I am looking at making a scintillator based fast neutron detector and have been looking at some of the PMT's for sale on E-bay. I am wondering how sensitive these are to ambient light damage as they have photo's on the site of them and some look like they are taken with a flash.