Single-W production to test triple gauge boson couplings at LEP

Abstract

We present a study of single-W production ($e^+e^-\to e^-\bar{\nu}_e W^+$) as a new probe of the anomalous couplings at the LEP energy region. We introduce simple cuts to separate the single-W process from W-pair production and have performed cross-section calculations using 4-fermion generator ``grc4f''. The cross-section of the single-W process is found to be large enough to detect at LEP experiments in the near future. In addition, a high sensitivity to the anomalous coupling of the $WW\gamma$ vertex is expected since the amplitude of the $WW\gamma$ diagram makes a dominant contribution in this process. We have found that the cross-section measurement of the single-W process in the LEP2 energy region can give complementary bounds on the anomalous couplings to those obtained from W-pair analysis.Comment: revised version, to appear in Physics Letters