Bounds on the W-Boson Electric Dipole Moment -Revisited

Abstract

Keeping in view the suggestion of Barr and Marciano [7] that the cut of procedure involves a good deal of uncertainity in the prediction of E.D.M. of W - boson, we have re-examined the earlier calculation by Marciano and Queijeiro [2] by replacing the Cut-off regularization process by BPHZ regularization[8]. This works in a clean and unambiguous manner without involving any approximation. We also examine apparently inapplicable approximations like using m(f) = m(f')in [2]. The bounds on lambda(w) and d(w) are significantly changed in all cases as compared with those reported in [2]. The necessary caution that is to be excercised while using approximations is explicitly pointed out. PACS number (s): 13.40. Em