Evidence for Hard-Gluon Bremsstrahlung in a Deep-Inelastic Neutrino Scattering Experiment

Data from $\nu N$ interactions in the Fermilab 15-ft bubble chamber show that the mean transverse momentum ($p_T$) of forward hadrons in the hadron c.m. system exceeds that of backward hadrons for $W^2>100\mathrm{}$ Ge${\mathrm{V}}^2$. Events with high ${\pi }_F$, a measure of forward $p_T$, tend to have planar hadron systems and show a three-jet structure in their angular energy flow; their number exceeds that expected in two-jet models. These observations are consistent with quantum chromodynamic predictions of hard-gluon bremsstrahlung.