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Hello,<br>
<br>
I have some first results of a simulation of the pile-up effects in the
tagger microscope readout. The effects studied are loss of counts
(efficiency) and loss of time resolution. The plots are below. I
think we want to keep the efficiency coming from pile-up effects from
dropping below 95%. Our spec for time resolution is 200ps. Both of
these criteria argue for keeping the microscope rates below 5 MHz per
channel. Based on the work that Alex showed on Monday, I would say
that 6cm reduction in pole width is an effective maximum, perhaps
somewhat less would be better. <br>
<a
href="http://zeus.phys.uconn.edu/halld/tagger/fp-microscope/rates-10-2009/effvsrate.gif"><br>
</a><a
href="http://zeus.phys.uconn.edu/halld/tagger/fp-microscope/rates-10-2009/effvsrate.gif">http://zeus.phys.uconn.edu/halld/tagger/fp-microscope/rates-10-2009/effvsrate.gif</a><br>
<a
href="http://zeus.phys.uconn.edu/halld/tagger/fp-microscope/rates-10-2009/tresvsrate.gif">http://zeus.phys.uconn.edu/halld/tagger/fp-microscope/rates-10-2009/tresvsrate.gif</a><br>
<br>
-Richard Jones<br>
<br>
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