Kevin Kramer
gave an update on g2n analysis:
Kevin and
Wolfgang Korsch have been checking the carbon asymmetries.
They are agree on the QE data, but
the results are not final. Corrections
need to be made to scalers and cuts.
Conclusion: false asymmetry is small
and consistent with zero.
Kevin worked
on a simulation to study errors associated with data
that has prescale factors. Concluded
that the error on the asymmetry
is less than the "scaler" asymmetry,
but more than the raw asymmetry
(due to correlation).
Kevin continued
his work on understanding how the gradient coils
affect the NMR signal fit. Part
of the problem comes from the fact that
he does not know the gradient or H1
very well. To solve the problem,
Kevin plotted the log of Chi squared
for the gradient vs H1. Using this
technique, H1 appear to be about 60
mG without the gradient coils on, and
H1 appears to decrease with increasing
gradient. To fit the NMR signals,
with gradient on, Kevin used a scaling
factor he got from an empirical fit.
Kevin checked
the water calibration constants with the constants obtained
from EPR measurements. The two
methods have reasonable agreement for
each of the cells used.
For the future
experiment, Kevin will work with Vince Sulkosky to
optimize the RF power by checking
the capacitors from the RF capacitor
box. Also the effect of the
preamplifier filters on the NMR shape will be
studied.
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