Weak-boson production by charm quarks

We propose a method to extract the charm structure function of the nucleon $c(x,Q^2=m_W^2)$ from measurements of the rapidity distribution of $W^{\pm }$ and $Z$ in $p\overline{p}$ collisions. The production of weak intermediate bosons via charm occurs at the few percent level at the Fermilab Tevatron and has in particular a strong influence on the important measurements of the ratio of $W$ and $Z$ events as $c\overline{s}\to W$ is expected to be much larger than $c\overline{c}\to Z$.