Proton polarization in inclusive production at 400 GeV/c

A search was made for polarization in inclusive proton production at 400 GeV/c, $P_t=0.96\mathrm{}$ GeV/c, $x=0.8\mathrm{}$. (Polarization in inclusive $\Lambda$ production is 10% in this region.) These protons were used to produce $\Lambda$'s at $p_t=0\mathrm{}$, and the polarization was found to be 0.003±0.006. This indicates that either the proton polarization is zero or that the $p-\Lambda$ spin transfer is zero, or both.