Renormalon structure in Bjorken sum rule

Leading-twist Bjorken polarised sum rule (BSR) Γ‾₁^p−n(Q²) is evaluated using its known renormalon structure. In addition, we add OPE terms with the dimension D=2,4, and fit this to experimental data for inelastic BSR in specific intervals of momenta, Q²≥Q_min², where Q_min²≈(1.7±0.3)GeV². Reasonable values of the pQCD coupling can be extracted only for specific choices of Q_min², but have in general, for other choices of Q_min², very large uncertainties and thus cannot be extracted in practice. On the other hand, if we fix the pQCD coupling to the known world average values, the D=2 and D=4 OPE terms can be determined within reasonable uncertainties dominated by the experimental uncertainties of the data.