Experimental determination of the evolution of the Bjorken integral at low Q2 -: art. no. 212001

We extract the Bjorken integral Gamma(1)(p-n) in the range 0.17<1.10 GeV2 from inclusive scattering of polarized electrons by polarized protons, deuterons, and He-3, for the region in which the integral is dominated by nucleon resonances. These data bridge the domains of the hadronic and partonic descriptions of the nucleon. In combination with earlier measurements at higher Q(2), we extract the nonsinglet twist-4 matrix element f(2).