SPHALERONS AT FINITE MIXING ANGLE - PERTURBATIVE ANALYSIS

In the limit of the vanishing mixing angle theta(W), the Weinberg-Salam theory admits two kinds of spherically symmetric, unstable classical solutions: the sphaleron and the bisphalerons. When theta(W) is finite, these solutions retain only an axial symmetry; they become spatially deformed. We study the influence of the mixing angle on the (bi)sphaleron solutions perturbatively, with the main emphasis on the U(1) gauge field, generated in the leading order approximation, and on the correction to the classical energy.