Relevance of some recent neutron-proton polarization data toTviolation at intermediate energies

Abstract

We comment on some neutron-proton polarization data taken by Leung, Kerth, and Surko at 520 and 600 MeV, and compare these data with $n\ensuremath{-}p$ asymmetry measurements taken by Cheng, MacDonald, Helland, and Ogden at 500 and 600 MeV. The two sets of data agree within experimental error, thus ruling out any $T$ asymmetry in $n\ensuremath{-}p$ scattering at intermediate energies greater than a few percent. We point out the relevance of this to a $T$-asymmetric nucleon-nucleon potential model developed by Bryan and Gersten.