Izvorni znanstveni članak
Study of leptonic and radiative b quark decays in the light of up-quark flavour changing contributions: multidoublet model
Surath Kumar Biswas
; Theoretical Physics Department, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700
V. P. Gautam
; Theoretical Physics Department, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700
Sažetak
The effective bsZ vertex may be influenced by tree uu˘Z vertex formed by a mixing with heavy exotic isosinglet up-type quarks. The electroweak penguin diagrams involving one insertion of the uu˘Z vertex have been considered and we have calculated the contribution arising from those diagrams using the fourth generation Cabbibo-Kobayashi-Maskawa matrix elements; also the applicability of the generalized Glashow-Iliopoulos-Maiani mechanism is considered. The additional effects of the heavy isosinglets are compared with the effects of exotic heavy isodoublets appearing in multi-generational models. We see that in the effective vertex amplitude, the up-flavour-changing contribution interferes constructively and destructively with the one loop-penguin diagrams with and without any insertion of flavour changing coupling, respectively.
Ključne riječi
Hrčak ID:
303511
URI
Datum izdavanja:
4.5.1997.
Posjeta: 434 *