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

• Received 21 June 2010

DOI:https://doi.org/10.1103/PhysRevC.82.027001