Measuring the uniformity of an electron beam

["Edwards, Richard W" <Richard.Edwards@PSS.Boeing.com>]

We've been asked to come up with a way to measure the energy deposition
across a relatively large surface from an electron beam system. The end
result is to determine whether or not there is uniform deposition
(+/-5%) across a two foot by two foot square. The system uses electrons
accelerated up to 30 keV (typically 17 keV). About all we have so far in
terms of total deposition is that it will deposit 10 microCoulombs per
cm2 in a 10 micron polymide layer during a typical application. We are
guessing that this application utilizes a 2 minutes exposure.

Some other problems. We're dealing with a sealed vacuum chamber with no
real ability to insert leads for powered systems or real time
monitoring. I assume our best bet is going to be to use TLDs placed on a
suitable backing.

Any experience or suggestions?

Rick Edwards, Analyst

The Boeing Company, Radiation Protection Technical Services Group
(425) 393-8250
>Richard.W.Edwards@Boeing.com