I just realized that I left a wrong plot in the logbook. Also the
rate during the last batch of ABS runs (700-800) is consistent with a
flow in the cell of M=2, not M=1. I.e. molecular.
Using the tof elastic filter it is very quick to do tof-only
analysis where the reconstruction efficiency must be high. The main
difference is that the timing cuts are truly cuts now: 40-60 channels (2-3
ns) at max, not 100-200.. Doing that and with an ADC cut, tof coplanarity
most always turns out ok automatically.
>From data of this weekend I "determined" the ABS flow comparing
TOF rates for ABS runs and unpol runs (where the flow is known and
is known to all go into the cell). The ABS flow (single spin state)
is 1.6E16 At/s which is close to expected.
With that flow and (similarly determined) gas temperature (120 +- 10K) I
compare the expected cross section (montecarlo) with the L/R tof data
after an adc cut, as a function of tof number. The normalization is done
on the montecarlo curve, and the difference between M=1 and M=2 is shown.
-- ________________________________________________________________________________ Tancredi Botto, phone: +1-617-253-9204 mobile: +1-978-490-4124 research scientist MIT/Bates, 21 Manning Av Middleton MA, 01949 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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