radiation measurements

[Elton Smith <elton@jlab.org>]

Hi Andi,

We spoke about measurements of doses during the radphi run yesterday. A
few questions came up as well as information about access. 

First, access. The barrel calorimeter extends beyond the lead glass frame,
although it does not touch the glass itself. However, the (light cover)
for the glass, which is attached to the frame is pushed in by the
calorimeter. Therefore, there is no air space between the barrel and the
cover. Inserting some TLDs in that area is possible, but not easy and
makes RadPhi personnel nervous without further specifics. If there is a
controlled access next week, it would be best if we can go in to take a
look at the setup.

Second, purpose. We talked about what would be learned about the
damage to fibers themselves. Gary Adams was there and suggested that
if one could obtain samples of the fiber, one could put them in at the
same place as the TLD, thereby checking the damage to the fiber for a
measured TLD dose. This might give more direct information on what you
would like to learn. Also, we should not disregard the present experience
with the start counter which has been used for all CLAS photon experiments
to date.

We can review all this next Wed. Cheers, Elton.

Elton Smith
Jefferson Lab
elton@jlab.org
(757) 269-7625