Hadronic structure of the weak neutral current. [Cross sections

Abstract

A comparison of neutral and charged current deep inelastic neutrino interactions is made in an experiment utilizing the Fermilab 15 ft bubble chamber. The ratio of neutral current events (NC) to charged current events (CC) is 0.35 +- .06 when the visible hadronic energy is greater than 10 GeV. The distributions of NC and CC in a new variable called u/sub vis/, which depends only on the observed hadrons, are given. From these distributions and the assumption that the x distribution is the same for NC and CC, it is concluded that for a NC y distribution of the form (1 - eta) + 3eta(1 - y)/sup 2/, eta = 0.12 +- 0.32. The ratio rho/sub NC/(rho/sub CC/) of neutron to proton cross sections in NC (CC) is studied and the quotient rho/sub NC//rho/sub CC/ = 0.7 +- 0.2. The distribution of hadrons in z/sub vis/, the scaled hadronic momentum, is given. The CC hadrons fit the predictions of the quark fragmentation functions D/sub u//sup ..pi../sup +//(z) and D/sub u//sup ..pi../sup -//(z) as given by Field and Feynman. The neutral current events fit the form (1 - lambda) D/sub u//sup ..pi../sup +//(z) + lambda D/sub d//sup ..pi../sup +//(z) for positivesmore » and (1 - lambda) D/sub u//sup ..pi../sup -//(z) + lambda D/sub d//sup ..pi../sup -//(z) for negatives with lambda = 0.56 +- 0.10 and a fit confidence level of 4 percent.« less