Summary of 1 day of data taking with the abs is that we have not measured
a significant asymmetry. So far both mine and chris analysis seem to point
in this direction.
We have no diagnostic on the MFT performance, on the other hand
we believe the sextupoles work (!). Therefore we could have any mixing
of states 1 and 2 in the target. Nominally, the MFT is set to perform 2-3
transitions only based on calculations/estimates which we don't have. With
the high holding field we have been using (350 gauss, which is almost its
maximum value), we can only lose if state 2 is present in the target due
to configuration mixing (state 2 will polarize negatively at high field)
Therefore, with vitaly, we have chosen to stil run a few shifts with the
MFT on, but a lower holding field (50 gauss). In this way we minimize the
effects due to possible presence of state 2. CCR is tuning the beam for
this lower h.f. Note that the holding field is now pointing at 135 deg, BR,
which means the "asymmetry" changes sign on a given sector.
Data taking should proceed as usual. We seem not to have any problems with
the compton, so please keep trying keeping the compton alive. all
components are critical so please spend a lot of time checking things.
For ABS questions, ask VZ, NM or me.
Assuming that the MFT rejects some of states 2 through a 2-3 transition
the above is an optimized scenartio.
Note however, that if for whatever reason we have only state 2 (so the
mft is very efficient in making what we don't want) we are going
to measure again zero.
irregardless of what your preference in thinking is, nobody knows if
its a or b.
In the second part of the plan we should switch the MFT completely off
and try to judge its performance from a possible asymmetry for a 50%
polarized beam (50% state 1 and 50% state 2) before recombination
effects. Note that in that case we may be better off in intensity
if all the mft does is 2->3+1->2.
-- ________________________________________________________________________________ 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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