Hall D Polarization Determination I. Physics Requirements

1. Hall D Polarization DeterminationI. Physics Requirements • Beam polarization is a required input to the partial wave analysis (PWA). • The PWA fit sensitivity to the value of p will differ from one channel to another, depending on the physical analyzing power A in that channel: • A and s0 have different sensitivities to small amplitude components. • There are cases where A is primary discriminator between solutions. • Systematics on acceptance will limit precision on measured s± • Limiting case: where A  ±1 then dp  few % would be useful. s± = s0 (1 ± pA) whereA [-1,1]. ds± dp |A| few %  few % s0

2. Hall D Polarization DeterminationII. Plans for Polarimetry CB spectral shape analysis • Primary method: • Expected precision: dp= 5% • Systematics may ultimately be pushed down to 2-3% • The expected initial 5% precision will be sufficient for many analysis channels and doing substantially better may await further motivation from actual physics analysis. requires cross checking with complementary methods