Re: FDC Tests

[Simon Taylor <staylor@jlab.org>]

Hi, all.

The signals from the Fe-55 are larger than most of the signals we are 
likely to see from the charged
particles passing through the detector during the GlueX experiment.  
However, the signals from cosmic rays have long tails in energy loss 
that correspond to large amplitude pulses some fraction of the time.   
The anode pulse height from the  Auger events from the Fe-55 peaks at 
about a factor of 5 above the peak for minimum ionizing particles and 
less than a factor of 2 above the peak for the lowest-momentum
protons we expect to see in the FDC.  So it seems to me that we can use 
the Fe-55 data to set a safe maximum for detection of particles whose 
energy loss is close to minimum ionizing where most the particles seen 
by the FDC will reside while still allowing for detection of  
low-momentum protons.

Simon