I gather from the message (way down) below that Chris2 has provided has
some helicity plus/minus cuts for cuts.C. So
root show_protons 1234 -c hp -d 1234 -c hn
super-imposes data from the same run 1234 with hp, hn. *NOTE* the variable
used in this cut is the spin direction at injection, let's not confuse that
with the spin flipper. Clearly at some point will need the product of the
two. There is no controls/epics/variables for the spin flipper at this time.
This gives me the opportunity to clarify something about charge
normalization:
* The dcct toroid provides a voltage signal \propto ring current
* The epics dcct variable is not "inhibited". That means it always
reads the charge, also when our hv is off or when coda is busy shipping
data (note we typically have ca. 10% deadtime at ca 250 Hz or so)
* The charge information is also fed to one of our VME scalers. Such
scaler DCCT variable is inhibited, so it counts only the right amount
charge, i.e. when the hv was all the way up and coda is not busy.
* The scaler dcct charge comes after a V2f conversion. The higher the ring
current, the higher the frequency and therefore the scaler value read out
(always in 1 second intervals)
* The following conversion should be used to go from scaler counts to mC
mC= p0+p1*scaler_count+p2*(scaler_counts)^2
p0=-0.865257
p1=0.00035756
p2=3.37238e-10
courtesy of C. DeAndrea and good up to 60 mA (we need better data above that).
since of course for us a rate of 1 mA measured in 1 second corresponds to 1 mC
of charge.
-- ________________________________________________________________________________ Tancredi Botto, phone: +1-617-253-9204 mobile: +1-978-490-4124 research scientist MIT/Bates, 21 Manning Av Middleton MA, 01949 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^On Fri, 22 Nov 2002, Chris Crawford wrote:
> the two cuts are -c hp (+ hel) and -c hn (- hel) > > Tancredi Botto wrote: > > > The full Blast Analysis meeting has been now moved to > > thursday 12/5 as many of the key players could not attend > > on tuesday. > > > > So let it be it ! > > > > -- > > ________________________________________________________________________________ > > 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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