New measurement of the production polarization and magnetic moment of theΞ−hyperon

We have measured the production polarization and magnetic moment of a sample of $89\times {10}^3{\Xi }^{-}$ hyperons produced in the inclusive reaction $p(400\mathrm{} \mathrm{GeV}/c)+\mathrm{Cu}\to {\Xi }^{-}+X$. The weighted average of the polarization is -0.070±0.008±0.010 at a $p_t$ of 0.63 GeV/c. The ${\Xi }^{-}\text{'}\mathrm{s}$ magnetic moment yields the value ${\mu }_{\Xi }=-0.661\mathrm{}\pm 0.036\pm 0.036$ nuclear magnetons. The first error is statistical, the second systematic.