Measurement of the Rotation Parameter R in Proton-Proton Scattering at 140 Mev

The proton-proton rotation parameter R has been measured at a laboratory energy of 140.5 Mev over a range of scattering angles θ₂ by means of a triple-scattering experiment. The following values were obtained: ${{θ}}₂(lab)=15^∘{}, {-}0.252±{}0.030; 20^∘{}, {-}0.227±{}0.028; 25^∘{}, {-}0.271±{}0.035; 30^∘{}, {-}0.146±{}0.037; 35^∘{}, {-}0.151±{}0.055;40^∘{}, {-}0.047±{}0.080$.