[G14_run] g14 statistics for K0 Lambda

[Reinhard Schumacher]

Hello All,
	Since this morning's (4-6-12) phone meeting, I revised the estimated 
statistics for the K0 Lambda data.  What we have in-hand so far is from 
the December/January period, runs 68188 to 68770.  I improved the 
estimate for the collimation of beam and for the total tagger count rate.

	See my revised slides posted on the April 6 meeting wiki page.

	I can reconcile my numbers with those in the proposal:  the proposal 
assumed a considerably thicker target and used a higher guesstimated 
total cross section.  That led to an estimate of 1200 to 1800 events per 
day, whereas I think we got only about 250 events per day.

	I conclude that we have only 7000 K0 Lambda events in hand, across all 
production angles and all beam energies.  This is down a factor of 4 
from my previous estimate, and there is still a factor of 2 uncertainty. 
  This number is consistent with Haiyun Lu's estimate based on a 
run-through of the partially-cooked data (See his talk on the meeting 
page).   Can anyone else double check this?  Thus, it looks to me at the 
present time like we don't have enough events to make physics analysis 
of this channel worthwhile.  Fortunately there are some fall-back 
options using other reaction channels.

	The run plan for the rest of the run period should be revisited to see 
whether we have a realistic chance to get anything out of the hyperon 
production channels.

Reinhard.
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Reinhard Schumacher         Department of Physics, 5000 Forbes Ave.
Carnegie Mellon University, Pittsburgh, PA 15213, U.S.A.
phone: 412-268-5177         web: www-meg.phys.cmu.edu/~schumach
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