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Hi GEN'ers,</div>
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There have been some numbers thrown around about what the polarization will be next week after the Hall C pass change so I just wanted to add some clarification. From my estimates assuming that Hall A is at 3pass and C is at 4pass and will share equally the
longitudinal polarization:</div>
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Optimal A Wien: +1.1 deg</div>
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Optimal B Wien: -30.7 deg</div>
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Optimal C Wien -61.7 deg</div>
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Sharing between A and C will give a Wien angle of -30.3 deg making Hall B extremely happy and A and C both off longitudinal by 31.4 deg. Cos(31.4deg)=0.854 and given a beam polarization of 0.84 we can expect somewhere in the neighborhood of 0.84*0.85=71.4%
give or take a couple of percent.</div>
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Caveat: the actual Wien setting chosen by the injector folks may be slightly off this estimate but I think it's safe to estimate a polarization of around 70%.</div>
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-Don</div>
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Donald Jones</div>
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Hall A/C Staff Scientist</div>
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Jefferson Lab</div>
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Newport News, VA</div>
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