We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.

Durham e-Theses
You are in:

On new physics in non-leptonic tree level b-quark decays and hadron-quark duality violations.

Tetlalmatzi Xolocotzi, Gilberto (2017) On new physics in non-leptonic tree level b-quark decays and hadron-quark duality violations. Doctoral thesis, Durham University.



We review the validity of the assumption of having no new physics in tree level b quark transitions $b\rightarrow q q' d$ and $b\rightarrow q q' s$ ($q, q'= u,c$).
In particular we test for possible deviations on the Wilson coefficients of the corresponding effective current-current operators with respect to their Standard Model values.
The allowed
new physics regions are determined using a global fit. We take into account constraints from different flavour observables calculated from the hadronic decays $B^0_d\rightarrow \pi\pi$, $B^0_d\rightarrow \rho\pi$, $B^0_d\rightarrow \rho\rho$, $B\rightarrow X_s \gamma$ and $B\rightarrow X_d \gamma$. We also include observables from neutral B meson mixing such as $\Delta \Gamma_s$ and the semileptonic asymmetries $a^{s,d}_{sl}$.
We show that deviations in the tree level Wilson coefficients of the order $\mathcal{O}(10\%)$ are consistent with state of the art experimental measurements. We study the implications of these deviations over the decay width $\Delta \Gamma_d$ of $B^0_d$ meson mixing, not measured yet by experiments, and over the precision of the CKM phase $\gamma$.
Our results
show that enhancements on $\Delta \Gamma_d$ by up to a factor of 3.6 with respect to the Standard Model value are allowed by data.
Moreover the effects on $\gamma$
can compete with the corresponding experimental precision $\mathcal{O}(6^{\circ})$.
Finally we explore for possible hadron-quark duality violations in the neutral $B$ and $D$ meson sectors.
This analysis includes constraints from
mixing observables and from the lifetimes of $B^0_d$ and $B^0_s$ mesons. We find that duality violations of $\mathcal{O}(20\%)$ can provide an explanation to the tension of several orders of magnitude between the Heavy Quark Expansion and experimental data in the observable $\Delta \Gamma_D$ of neutral $D$ meson mixing.

Item Type:Thesis (Doctoral)
Award:Doctor of Philosophy
Keywords:High Energy Physics, quark-flavour physics, new physics, B-meson physics.
Faculty and Department:Faculty of Science > Physics, Department of
Thesis Date:2017
Copyright:Copyright of this thesis is held by the author
Deposited On:16 Jan 2017 12:09

Social bookmarking: del.icio.usConnoteaBibSonomyCiteULikeFacebookTwitter