相关论文: Towards a Precision Determination of alpha in B \t…
An isospin analysis of $B\to \pi\pi$ decays yields $\sin 2\alpha$, where $\alpha$ is the usual CKM angle $\alpha\equiv {\rm arg} [-V_{td} V_{tb}^\ast/(V_{ud}V_{ub}^\ast)]$ without hadronic uncertainty if isospin is a perfect symmetry. Yet…
An isospin analysis of $B\to\pi\pi$ decays yields $\sin 2\alpha$, where $\alpha$ is the usual CKM angle $\alpha\equiv arg [-V_{td}V_{tb}^\ast /(V_{ud}V_{ub}^\ast)]$, without hadronic uncertainty if isospin is a perfect symmetry. Isospin,…
Recent experimental results on $B\to\rho\rho$ decays indicate that the CP asymmetry $S_{\rho^+\rho^-}$ will give an interesting determination of $\alpha=\arg[-(V_{td}V_{tb}^*)/(V_{ud}V_{ub}^*)]$. In the limit when the $\rho$ width is…
I present two disparate examples of isospin violation in hadronic B-decays. In the first, the presence of \rho^0-\omega mixing in the decay B^\mp\to\rho^\mp\rho^0(\omega)\to\rho^\mp\pi^+ \pi^- permits the extraction of sgn(\sin \alpha),…
Isospin analysis has been used to constrain the CP-asymmetries in B -> pi pi decays. In particular correlation between a weak phase \theta and a strong phase \delta is obtained. Further using the experimental values for the CP-average…
The current results on B to pipi decays and SU2 constraints on the Unitarity Triangle angle alpha or phi_2 from the B-factories are summarised. Based on these measurements, predictions of the isospin analysis constraints at the end of the…
The approximate symmetry of the strong interactions under isospin transformations is among the most precise tools available to control hadronic matrix elements. It is crucial in extracting fundamental parameters, but also provides avenues…
A clean determination of the angle $\alpha$ of the unitary triangle from $B\to \pi\pi$ decays requires an isospin analysis. If the $B \to \pi^0\pi^0$ and $\bar B \to \pi^0\pi^0$ decay rates are small it may be hard to carry out this…
Isospin and flavor SU(3) set stringent bounds on penguin pollution in $B^0(t)\to \rho^+\rho^-$, providing a theoretically precise determination of $\alpha\equiv \phi_2 $, $\alpha = (91\pm 7_{\rm exp}\pm 3_{\rm th})^\circ$. Isospin breaking…
The Standard Model constraints on alpha which can be derived from the B-> pipi decays are revisited in some depth. As experimental inputs, the three branching ratios, the two CP parameters Spipi and Cpipi and/or the value of alpha as…
We present an {\it algebraic} isospin approach towards a more straightforward and model-independent determination of the weak phase $\alpha$ (or $\phi_2$) and QCD penguin pollution in $B\to \pi\pi$ decays. The world averages of current…
In terms of effective field theory and mixed propagator approach, we show that there is a larger hidden effect of isospin breaking in $\rho^0\to\pi^0\gamma$ decay due to an $\omega$ exchange, $\rho^0\to\omega\to\pi^0\gamma$. The branching…
Theoretical errors in the extraction of alpha from B -> pi^+ pi^-, rho^+ rho^-, rho pi decays are usually given in terms of upper bounds on alpha_eff-alpha obtained from isospin or from SU(3) relations, where alpha_eff is measured through…
We show that a consequence of isospin symmetry, recently discovered in mirror conjugated one-nucleon decays, can be extended to mirror-conjugated $\alpha$-particles decays, both virtual and real. For virtual $\alpha$-decays of bound mirror…
For direct CP-violation in $K\to\pi\pi$ decays, the usual isospin-breaking effects at the percent level are amplified by the dynamics behind the $\Delta I=1/2$ rule and conventionally encoded in $\Omega_{\rm IB}$ parameters. The updated…
Isospin breaking correction to the $\Delta I = {1/2}$ decay of $K\to\pi\pi$ generates a large enough contribution to $\epsilon'$ through an induced $\Delta I = {3/2}$ amplitude in $K_L$ decay. Aside from the $\pi$-$\eta$ and $\pi$-$\eta'$…
The potential of constraints on the angle alpha of the Unitarity Triangle from studies of B0 -> pi+ pi- pi0 decays is reviewed. The experimental inputs needed for an isospin analysis are starting to become available. The precision of…
In a model of isospin symmetry breaking we obtain the ($e^{-} e^{+} \rightarrow \pi^{-} \pi^{+}$) amplitude $Q$ and the isospin $I=0$ and $I=1$ relative phase $\psi$ at the $\phi (1020)$ resonance in aproximate agreement with experiment.…
We point out that the measurement of just the two branching fractions \linebreak $B(K^+\to\pi^+\nu\bar\nu)$ and $B(K_L\to\pi^0\nu\bar\nu)$ can in a theoretically clean manner determine $\sin 2\beta$ almost independently of $m_t$ and…
Quasi two-body decays B^0(t)-> a_1^{+-}(1260) pi^{-+} identified by four charged pions determine a phase alpha_eff, which is equal to the weak phase alpha in the limit of vanishing penguin amplitudes. Applying flavor SU(3) to these decays…