Corrections for the polarization-dependent efficiency and new neutron-proton analyzing power data at 7.6 MeV

摘要

We present new corrections for the polarization-dependent efficiency (PDE), which introduces a false asymmetry into measurements of n-p analyzing power Ay(θ) caused by double scattering in the neutron side detectors. To accomplish this, we created a new database of 12C(n⃗,n) Ay(θ) by using a combination of fits to data, phase-shift analysis, and R-matrix analysis. Our recorrection for PDE of previously reported n-p Ay(θ) data at 7.6 and 12.0 MeV and new data at 7.6 MeV indicate that we have achieved a superior representation of 12C(n⃗,n). Our results continue to suggest a possible charge dependence of the pion-nucleon coupling constant.