Oblique Corrections To The W Width

Abstract

The lowest-order expression for the partial $W$ width to $e\nu ,\Gamma (W\to e\nu )=G_{\mu }{M}_W^3/(6\pi \sqrt{2})$, has no oblique radiative corrections from new physics if the measured $W$ mass is used. Here $G_{\mu }=(1.16639\pm 0.00002)\times 10^{-5}$ GeV/$c^2$ is the muon decay constant. For the present value of $M_W=(80.14\pm 0.27)$ GeV/$c^2$, and with $m_t=140$ GeV$/c^2$, one expects $\Gamma (W\to e\nu )=(224.4\pm 2.3)$ MeV. The total width ${\Gamma }_{\mathrm{tot}}(W)$ is also expected to lack oblique corrections from new physics, so that ${\Gamma }_{\mathrm{tot}}(W)/\Gamma (W\to e\nu )=3+6[1+\{{\alpha }_s(M_W)/\pi \}]$. Present data are consistent with this prediction.

Comments: 15 pages (LaTeX), one PostScript figure not included (available upon request)