ZEUS HERAII data, see Table \[tab:pol\], is $185 < Q^2 < 51\,200$GeV$^2$, $0.0063 < x_{\rm Bj} < 0.75$ for NC and $200 < Q^2 < 60\,000$GeV$^2$, $0.0078  < x_{\rm Bj} < 1.0$ for CC interactions.

The electron beam in HERA became naturally transversely polarised through the Sokolov-Ternov effect [@sovpdo:8:1203]. The characteristic build-up time in HERA was approximately 40 minutes. Spin rotators on either side of the ZEUS detector changed the transverse polarisation of the beam into longitudinal polarisation in front of the interaction point and subsequently back to transverse polarisation. The electron-beam polarisation was measured using two independent polarimeters, the transverse polarimeter (TPOL) [@Baier:1969hw; @nim:a329:79] and the longitudinal polarimeter (LPOL) [@nim:a479:334]. Both devices exploited the spin-dependent cross section for Compton scattering of circularly polarised photons from electrons. The luminosity and polarisation measurements were made over time scales that were much shorter than the polarisation build-up time.

The total integrated luminosity for the ZEUS HERAII samples is about $300\,{\,\text{pb}^{-1}}$. The data were almost evenly divided between positive and negative beam polarisation. The ZEUS cross sections for polarised electron beams were published previously [@ZEUS2NCe; @ZEUS2NCp; @ZEUS2CCe; @ZEUS2CCp]. For this analysis, the polarisation values were corrected using the final information on the polarimeters 