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#### This entry is a followup to: 44658

keyword=detail on time estimate for thcm=-50

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Just a note to further understand Mark's time (charge) estimate needed for this
point (since it seemed different than what I had expected)...
Mark's analysis gives:
- coll out (Run 2447): with tight W, Q2 and pid cuts:
315 events/mC
This means 9.2 C of "coll out" running needed (gives 2.9 M "good" events)

To evaluate how to count the 3.5 Coulombs already acquired with 6 msr collimators
in place, there are actually 2 estimates:
1. using analysis of last night's Run 2438:
175 events/mC
so 3.5 Coulombs scales by (175/315) => 1.9 C "equivalent"

2. using analysis of May run (run 1416):
230 events/mC
so 3.5 Coulombs scales by (230/315) => 2.5 C "equivalent"

Therefore, the two estimates of how much "open (no) collimator" running needed
at this point are:
1.   9.2 C - 1.9 C = 7.3 C
or
2.   9.2 C - 2.5 C = 6.7 C

CONCLUSION:  Split the difference, go for ** 7.0 C ** with no collimators.

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