Skip to Main content Skip to Navigation
Journal articles

Determination of the pion-nucleon coupling constant and scattering lengths

Abstract : We critically evaluate the isovector GMO sum rule for forward pion-nucleon scattering using the recent precision measurements of negatively charged pion-proton and pion-deuteron scattering lengths from pionic atoms. We deduce the charged-pion-nucleon coupling constant, with careful attention to systematic and statistical uncertainties. This determination gives, directly from data a pseudoscalar coupling constant of 14.11+-0.05(statistical)+-0.19(systematic) or a pseudovector one of 0.0783(11). This value is intermediate between that of indirect methods and the direct determination from backward neutron-proton differential scattering cross sections. We also use the pionic atom data to deduce the coherent symmetric and antisymmetric sums of the negatively charged pion-proton and pion-neutron scattering lengths with high precision. The symmetric sum gives 0.0012+-0.0002(statistical)+-0.0008 (systematic) and the antisymmetric one 0.0895+-0.0003(statistical)+-0.0013(systematic), both in units of inverse charged pion-mass. For the need of the present analysis, we improve the theoretical description of the pion-deuteron scattering length.
Complete list of metadata
Contributor : Dominique Girod Connect in order to contact the contributor
Submitted on : Tuesday, December 4, 2007 - 2:49:05 PM
Last modification on : Tuesday, January 25, 2022 - 12:48:10 PM

Links full text



T. E. O. Ericson, B. Loiseau, A. W. Thomas. Determination of the pion-nucleon coupling constant and scattering lengths. Physical Review C, American Physical Society, 2002, 66, pp.014005. ⟨10.1103/PhysRevC.66.014005⟩. ⟨in2p3-00193736⟩



Record views