Width Effects on Near Threshold Decays of the Top Quark t-> cWW,cZZ and of Neutral Higgs Bosons

Abstract

The nonzero widths of heavy particles become significant when they appear in the final state of any decay occurring just around its kinematical threshold. To take into account such effects, a procedure, called the convolution method, was proposed by Altarelli, Conti and Lubicz. We expand their study which included only threshold effects for t-> bWZ in the standard model. We discuss finite width effects in the three body decays t-> cWW,cZZ and A^0(h^0)->tbW in the type III version of a two Higgs doublet model. In particular, we find a substantial enhancement in the decay t->cZZ, which brings its branching ratio to BR(t->cZZ)~10^-3, and in the decay A^0->tbW, which, unlike the h^0 case, becomes competitive with the A^0 two-body decay modes.

18 pages, 6 figures, uses axodraw.sty, minor correction in few sentences, one equatin and 3 references added. To be published in Phys.Rev.D

References in corpus (1)

• The flavor-changing rare top decays $t\to cVV$ in topcolor-assisted technicolor theory

Cited by in corpus (17)

• New Physics effects in the flavor-changing neutral couplings of the Top quark
• Rare Decay of the Top t->c l lbar and Single Top Production at International Linear Collider
• Rare Decay of the Top t -> cgg in the Standard Model
• Top Quark FCNC Decay to 125GeV Higgs boson in the Littlest Higgs Model with T-parity
• Rare and exclusive few-body decays of the Higgs, Z, W bosons, and the top quark
• The convolution formula for a decay rate
• Higgs couplings and new signals from Flavon-Higgs mixing effects within multi-scalar models
• Collider signals of a composite Higgs in the Standard Model with four generations
• Higgs mediated Double Flavor Violating top decays in Effective Theories
• Top quark rare three-body decays in the littlest Higgs model with T-parity
• Rare top-quark decays $t\to cg(g)$ in the aligned two-Higgs-doublet model
• Factorization in the model of unstable particles with continuous masses
• Factorization method in the model of unstable particles with a smeared mass
• Lepton pair emission in the top quark decay $t\to b{W}^{+}{\ell }^{-}{\ell }^{+}$
• CKM-suppressed top quark decays t -> q + W in the SM and beyond
• Threshold Effects in the Decay of Heavy b' and t' Quarks
• Unparticle effects in rare (t -> c g g) decay