arXiv subjects
Publications and source records attributed to Fulvia De Fazio.
Recent data for B decays to two light vector mesons show that the longitudinal amplitude dominates in $B^0 \to ρ^+ ρ^-$, $B^+ \to ρ^+ ρ^0$, $ρ^0 K^{*+}$ decays and not in $B^0 \to ϕK^{*0}$, $B^+ \to ϕK^{*+}$. We consider rescattering mediated by charmed resonances, finding that in $B \to ϕK^*$ it can be responsible of the suppression of the longitudinal amplitude. A similar result is found for $B \to ρK^{*}$.
I briefly review some results and open questions in the analysis of CP violation in the B sector.
Nonleptonic $B$ to charmonium decays generally deviate from the factorization predictions. We study rescattering effects mediated by intermediate charmed mesons in this class of decay modes and, in particular, we consider $B^- \to K^- h_c$ with $h_c$ the $J^{PC}=1^{+-}$ $\bar c c$ meson, relating this mode to $B^- \to K^- χ_{c0}$. We find ${\cal B}(B^- \to K^- h_c)$ large enough to be measured at the $B$ factories, hence this process could be used to study the poorly known $h_c$.
We use light-cone QCD sum rules to evaluate the strong coupling $g_{f_0 K^+ K^-}$ which enters in several analyses concerning the scalar $f_0(980)$ meson. The result: $6.2\le g_{f_0 K^+ K^-}\le 7.8$ GeV is larger than in previous determinations.
We discuss the validity of factorization for exclusive two-body B to charmonium transitions. In particular, we consider the role of non factorizable corrections in selected two-body modes.
I briefly review the description of inclusive heavy hadron decays based on the inverse heavy quark mass expansion. In particular, I consider the transition $B \to X_u \ell ν$ and the problem of extracting $V_{ub}$, mainly as far as the separation from the background represented by $b \to c$ modes is concerned. I also discuss how to obtain complementary information from the decay mode $B \to X_s γ$.
We use QCD sum-rules to study the decays $ϕ\to ηγ$ and $ϕ\to η^\prime γ$, obtaining ${\cal B}(ϕ\to ηγ)=(1.15 \pm 0.2) 10^{-2}$ and ${\cal B}(ϕ\to η^\prime γ)=(1.18 \pm 0.4) 10^{-4}$, in very good agreement with existing experimental data. We also discuss the issue of $η-η^\prime$ mixing, predicting the $η$ and $η^\prime$ decay constants in a mixing scheme in the quark-flavour basis.
I briefly describe recent developments in the theoretical analysis of non leptonic and semileptonic B decays. For non leptonic transitions, I focus on factorization, from the naive formulation to the most recent achievements. As for semileptonic decays, I mainly consider B transitions to excited charmed states.
I discuss the heavy quark expansion for the inclusive widths of heavy-light hadrons, which predicts quite well the experimental ratios of B_q meson lifetimes. As for $Λ_b$, current determinations of ${\cal O}(m_b^{-3})$ contribution to $τ(Λ_b)$ do not allow to explain the small measured value of $τ(Λ_b)/τ(B_d)$. As a final topic, I discuss the implications of the measurement of the B_c lifetime.
We review some aspects of weak decays of hadrons containing one heavy quark. The main emphasis is on $B$ physics, in particular in the framework of the Heavy Quark Effective Theory.