a Measurement of Boson-Photon and Boson-Photon Cross Sections in the Muon Channel in 1.8 Tev Antiproton - Collisions.

We have measured the production cross sections x decay branching ratios for W + gamma and Z + gamma in the muon channel in sqrt{s} = 1.8 TeV p -p collisions, from 3.54 +/- 0.24 pb^{-1} of muon W and Z data from the CDF 1988-89 Tevatron collider run. For photons in the central region (|eta| < 1.1) of the CDF detector with transverse energies E_sp{T}{gamma} > 5.0 GeV and lepton-photon angular separation Delta R_{l_gamma } > 0.7, 5 W_{gamma } candidates and 2 Z_{ gamma} candidates were observed. From these events, the sigma cdot BR(W + gamma) and sigma cdot BR(Z + gamma) cross sections for the muon samples are measured, and compared with Standard Model predictions. We also determined the cross section ratios, W_{gamma}/W, Z _{gamma}/Z and W _{gamma}/Z_{gamma }, which, along with the previous CDF measurement(s) of the W/Z cross section ratio provide new insight on the Standard Model, and are sensitive to anomalous couplings of the W and Z bosons. Using the W_{ gamma} and Z_{gamma } absolute cross section measurements, the absence of an excess of hard photons accompanying W and Z boson production enables us to obtain direct limites on anomalous WW_{gamma} , ZZ_{gamma} and Z_{gammagamma} couplings. For saturation of unitarity, these experimental limits impose constraints on possible internal (composite) structure for the W and Z bosons with compositeness scale sensitivity up to Lambda_{W } ~ 1 TeV and Lambda _{Z} ~ 250-500 GeV, respectively. These compositeness scale limits probe the possible internal structure of the W to {~}<2 times 10^{-4 }fm and internal structure of the Z to {~}<4-7 times 10^{-4} fm. Limits on the anomalous W_{gamma} and Z_{gamma} couplings also impose constraints on the higher order static and transition EM moments of the W and Z boson, respectively. The muon channel measurements were combined with those made from the electron channel to arrive at mu + e combined sigma cdot BR(W) + gamma) and sigma cdot BR(Z + gamma) absolute cross sections, and limits on the anomalous couplings for combined mu + e W_ {gamma} and Z_{ gamma}.