[Halld-cal] amplification factor for Bcal electronics

Elton Smith elton at jlab.org
Fri May 25 13:21:42 EDT 2012

Hi all,

I have posted various plots on the elog. From them, I think we need to 
reduce the gain to a level similar to that shown for the Vover=0.6 V 
data at the 35% point. From Andrei's plot of average amplitude vs bias 
overvoltage, we get the following ratios:

( Vover=0.6/Vover=1.2) = 1100/2550 = 0.43
(Vover=0.9/Vover=1.2) = 1800/2550 = 0.71.

Assuming we are aiming for maximum at 2 GeV, we need to take the energy 
ratio. At the 35% point, our energy was 0.34*5.551 = 1.89 GeV.

Assuming we want to operate at Vover=1.2 V, then the gain factor should 
be 0.43x0.95 = 0.41. That is the gain should be reduced by a factor of 2.5.

We can use these number to guide the discussion this afternoon.

Thanks, Elton.

Elton Smith
Jefferson Lab MS 12H5
12000 Jefferson Ave
Suite #16
Newport News, VA 23606
(757) 269-7625
(757) 269-6331 fax

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