Rapidity Correlations in $W\gamma$ Production at the Tevatron

Abstract

We study the correlation of photon and charged lepton pseudorapidities, $\eta (\gamma )$ and $\eta (\ell )$, $\ell =e,\mu$, in $p\bar{p}\to W^{\pm }\gamma +X\to {\ell }^{\pm }p{\text{/}}_T\gamma +X$ at the Tevatron. In the Standard Model, the $\Delta \eta (\gamma ,\ell )=\eta (\gamma )-\eta (\ell )$ differential cross section is found to exhibit a pronounced dip at $\Delta \eta (\gamma ,\ell )\approx \mp 0.4$, which originates from the radiation zero present in $q{\bar{q}}^{\prime }\to W\gamma$. The sensitivity of the $\Delta \eta (\gamma ,\ell )$ distribution to higher order QCD corrections, non-standard $WW\gamma$ couplings, and the cuts imposed is explored. The $\Delta \eta (\gamma ,\ell )$ distribution is compared with other quantities which are sensitive to the radiation zero.

LaTeX, 9 pages, 3 postscript figures in a separate uuencoded file, FSU-HEP-930727, to appear in the Proceedings of the Workshop ``Physics at Current Accelerators and the Supercollider'', Argonne National Laboratory, June~2 --~5, 1993