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delta_cuts
Analysis with tight delta cuts 04/30/06
Regions of phase space could be selected
where Pauli blocking and FSI have less of an effect on the
results. The idea was to be able to rescue our deuterium data,
which seems to be very model dependent, and make the ratios with
hydrogen more significant.
Basically, the idea is to sacrifice some statistics to reduce the model
uncertainty.
Delta cuts were used to select low hsdelta and ssdelta events, so that
the recoiling neutron has, on average, larger momentum. The
results in this region of phase space are less dependent on the model
for Pauli blocking and FSI. In hindsight, a more appropriate cut
may be on the missing mass, which is also closely related to the
neutron momentum. A suitable cut might be mmx>0.96, for
example. However, with the delta cuts only, we can check that the
missing mass distribution is not shifted between data and SIMC.
The missing mass shifts for all targets, except for gold, seem to have
good agreement without any missing mass shifts. I think it is
exciting that the distributions (omega, Q2, thetapq, etc) seem to have
good agreement between SIMC and the data. Furthermore, the SIMC
distributions do not really change much when Pauli blocking and FSI are
turned on. One notable exception is the deuterium missing mass
plots at the lowest Q2 (no
Pauli or fsi, with
Pauli and FSI). So, this setting may not be able to be
rescued with this approach, unless we can make corrections to our Pauli
blocking model for deuterium.
Conclusions: With either tight delta cuts or a suitable missing
mass cut, we seem to be select samples of events with reduced model
uncertainty. The lowest Q2 deuterium setting and the gold data
appears to be the exceptions.
Results without missing mass shifts, Pauli blocking or FSI weight
Missing mass plots
Results without missing mass shifts, but with
Pauli blocking and FSI weight (delta=2.0)
Missing mass plots
