PS counters

[Alexander Somov <somov@jlab.org>]

Hello Hrachya,

I am trying to summarize the pair spectrometer
simulation which we have done by the tagger review.

I have a quick question: are you planning to further 
optimize the layout of scintillator counters (in the
simulation I want to have the most 'realistic' geometry )?

My main concern is that the energy resolution of the
beam photons is very nonuniform over the energy range;
it's much worse for the 2 mm wide WSF counter (at 8.25 GeV) 
where the beam spot size dominates. 
For example we can think of using a larger energy range 
for the FSF counters between 3-6 GeV and lower energy for
the WSF counters, i.e., use 3.25 and 6.25 GeV WSF counters.
The width of 6.25 GeV WSF counter is 0.34 cm, which is
comparable with the beam spot size. If we use 15 bins per
1 GeV for the FSF counters we will need just one more FADC,
3 in total instead of 2  (you mentioned that 15 bins per GeV
for the FSF counter would probably be sufficient (?))
Ok, here are just thoughts.

Thanks,
        Sascha