Re: crystal curing (fwd)

[Simon Taylor <staylor@jlab.org>]

Some information about curing crystals with light from the Mainz A4 group.

Simon


---------- Forwarded message ----------
Date: Fri, 5 Oct 2007 12:35:35 +0200 (CEST)
From: Sebastian Baunack <baunack@kph.uni-mainz.de>
To: Simon Taylor <staylor@jlab.org>
Subject: Re: crystal curing


Hi Simon,

For the crystal curing:
We use fluorescent lamps, so called "energy saving lamps" of the type
"Osram Dulux L 24W/67 blue". They give a light flux of 550 lm and a light
power of 40 cd. As the name says, they produce blue light.

We install the lamps usually after four weeks of beam, so practically
after two runs. As far as I can judge it, the crystals are recovered
fully. I can see that on the calibration: The high voltages after curing
go back to the same values they had after the preceeding curing.

There is a NIM paper on the PbF2 crystals which includes some words on the
curing:

"Radiation resistance and optical properties of lead fluoride Cherenkov
crystals"
P. Achenbach et al. 1998,
Nucl.Instrum.Meth.A416:357-363,1998.

You can find this article with Spires. If there's a problem, you can find
the postscript file also on our webpage ("Veröffentlichungen").