We present a model for the decay D+ --> K- pi+ pi+. The weak interaction part of this reaction is described using the effective weak Hamiltonian in the factorisation approach. Hadronic final state interactions are taken into account through the Kpi scalar and vector form factors fulfilling analyticity, unitarity and chiral symmetry constraints. The model has only two free parameters that are fixed from experimental branching ratios. We show that the modulus and phase of the S wave thus obtained agree nicely with experiment up to 1.55 GeV. We perform Monte Carlo simulations to compare the predicted Dalitz plot with experimental analyses. Allowing for a global phase difference between the S and P waves of -65 degrees, the Dalitz plot of the D+ --> K- pi+ pi+ decay, the Kpi invariant mass spectra and the total branching ratio due to S-wave interactions are well reproduced.
This paper is focused on two issues: the Kπspectrum near threshold - the kappa problem -, and the piπspectrum between 1.2 and 1.5 GeV/(c^2) -- the f_0(1370) problem. Both problems will be analysed from the perspective of the $D$ meson decays, with some additional information from $τ$ and B decays.
Recently, the tau --> K pi nu_tau decay spectrum has been measured by the Belle and BaBar collaborations. In this work, we present an analysis of such decays introducing a dispersive parametrization for the vector and scalar Kpi form factors. This allows for precise tests of the Standard Model. For instance, the determination of f_+(0)|V_{us}| from these decays is discussed. A comparison and a combination of these results with the analyses of the K_{l3} decays is also considered.
The slope and curvature parameters of the $Kπ$ vector form factor, $F_+^{Kπ}$, are fitted to the data on $\tauKpi$ and $K_{l3}$ decays yielding $λ_+'=(25.49 \pm 0.31) \times 10^{-3}$ and $λ_+"= (12.22 \pm 0.14) \times 10^{-4}$. The pole position of the $K^*(892)^\pm$ is found to be at $m_{K^*(892)^\pm}= 892.0\pm 0.5$ MeV and $Γ_{K^*(892)^\pm}= 46.5 \pm1.1$ MeV. The phase-space integrals relevant for $K_{l3}$ analyses and the $P$-wave isospin-1/2 $Kπ$ phase-shift threshold parameters are also calculated.
Constraining CKM parameters from charmless hadronic B decays requires methods for addressing the hadronic uncertainties. A complete technique is presented, using relations between amplitudes in the B, Bs -> pipi, Kpi, KK system obtained in the exact SU(3) symmetry limit, without having to neglect annihilation/exchange topologies. Naive SU(3)-breaking effects in the decay amplitudes are taken into account, through the inclusion of pi and K decay constants in the normalisations and conservative theoretical errors. Already with the limited set of observables currently available, significant const…
A subtracted dispersive representation of the $Kπ$ vector form factor, $F_+^{Kπ}$, is used to fit the Belle spectrum of $\tauKpi$ decays incorporating constraints from results on $K_{l3}$ decays. Through the use of three subtractions, the slope and curvature of $F_+^{Kπ}$ are obtained directly from the data yielding $λ_+'=(25.49 \pm 0.31) \times 10^{-3}$ and $λ_+"= (12.22 \pm 0.14) \times 10^{-4}$. The phase-space integrals relevant for $K_{l3}$ analyses are calculated. Additionally, from the pole position on the second Riemann sheet the mass and width of the $K^*(892)^\pm$ are found to be $m_…
Heavy flavour decay to light hadrons is the key to understanding many aspects of the SM from CP violation to strong dynamics. It is often presumed in line with the simple quark spectator model of D decay to Kpipi that the Kpi system has only I=1/2. E791 have recently presented an analysis of their results on D+ to (K-pi+)pi+ using a generalised isobar picture of two body interactions. While higher Kpi waves are described by sums of known resonances, the S-wave amplitude and phase are determined bin-by-bin in Kpi mass. The phase variation is found not to be that of K-pi+ elastic scattering. Thi…
A sum rule relation is proposed for direct CP asymmetries in $B\to Kπ$ decays. Leading terms are identical in the isospin symmetry limit, while subleading terms are equal in the flavor SU(3) and heavy quark limits. The sum rule predicts $A_{\rm CP}(B^0\to K^0π^0)=-0.17 \pm 0.06$ using current asymmetry measurements for the other three $B\to Kπ$ decays. A violation of the sum rule would be evidence for New Physics in $b\to s\bar qq$ transitions.
The $Kπ$ vector form factor, $F_+^{Kπ}$, used to reproduce the Belle spectrum of $\tauKpi$ decays is described by means of a three-times subtracted dispersion relation also incorporating constraints from $K_{l3}$ decays. The slope and curvature of $F_+^{Kπ}$ are fitted to the data yielding $λ_+'=(25.49 \pm 0.31) \times 10^{-3}$ and $λ_+"= (12.22 \pm 0.14) \times 10^{-4}$. The pole parameters of the $K^*(892)^\pm$ are found to be $m_{K^*(892)^\pm}= 892.0\pm 0.5$ MeV and $Γ_{K^*(892)^\pm}= 46.5 \pm1.1$ MeV. The phase-space integrals relevant for $K_{l3}$ analyses and the $P$-wave isospin-1/2 $Kπ…
Simple flavor symmetry argument without QCD dynamics shows why CP violation observed in neutral $B$ to $Kπ$ decays is absent in charged B decays where tree diagram final state has two $u$ quarks satisfying Pauli principle. Entanglement preserves short range symmetry correlations after separation into two mesons. Pauli principle and symmetries require totally flavor-symmetric tree diagram final state. $ππ$ isospin state with I=2 already is flavor symmetric and suffers no symmetry constraint. Strange flavor-symmetric state with V spin V=2 is linear combination of $Kπ$ and $K η$ with probability …
Employing results from a recent determination of the scalar KPi form factor F_0^KPi within a coupled channel dispersion relation analysis \cite{JOP01}, in this work we calculate the slope and curvature of F_0^KPi(t) at zero momentum transfer. Knowledge of the slope and curvature of the scalar KPi form factor, together with a recently calculated expression for F_0^KPi(t) in chiral perturbation theory at order p^6, enable to estimate the O(p^6) chiral constants C_12^r=(0.3 +- 5.4)10^-7 and (C_12^r+C_34^r)=(3.2 +- 1.5)10^-6. Our findings also allow to estimate the contribution coming from the C_i…
Dispersive representations of the Kpi vector and scalar form factors are used to fit the spectrum of tau ---> K pi nu_tau obtained by the Belle collaboration incorporating constraints from results for K_l3 decays. The slope and curvature of the vector form factor are obtained directly from the data through the use of a three-times-subtracted dispersion relation. We find $λ_+'=(25.49 \pm 0.31) \times 10^{-3}$ and $λ_+"= (12.22 \pm 0.14) \times 10^{-4}$. From the pole position on the second Riemann sheet the mass and width of the $K^*(892)^{\pm}$ are found to be $m_{K^*(892)^\pm}=892.0\pm 0.5$~M…
We update the profile of the CKM matrix. The apex (rhobar,etabar) of the Unitarity Triangle is given by means of a global fit. We propose to include therein sin2alpha from the CP-violating asymmetries in B0->rho+rho-, using isospin to discriminate the penguin contribution. The constraint from epsilon'/epsilon is briefly discussed. We study the impact from the measurement of the rare decay K+->pi+nunu-bar, and from a future observation of KL->pi0nunubar. The B system is investigated in detail, beginning with 2beta+gamma and gamma from B0->D(*)+-pi-+ and B+->D(*)0K+. A significant part of this p…
It has been argued recently that transverse asymmetries that are expected to be shielded from the presence of the S-wave (Kpi) pairs originating from the decay of a scalar K0* meson, are indeed affected by this pollution due to the impossibility to extract cleanly the normalization for these observables. In this short note we show how using folded distributions, which is nowadays the preferred method to obtain the information from the 4-body decay mode B-> K*(-> Kpi) l+l-, one can easily bypass this problem and extract the clean observables P_{1,2,3} and also P'_{4,5,6} in a way completely fre…
The experimental results published by KTeV and the preliminary results from NA48 concerning the slope of the Kpi scalar form factor suggest a significant discrepancy with the prediction of the Callan-Treiman low energy theorem once interpreted within the Standard Model. In this talk, we will show how this discrepancy could be explained as a first evidence of the direct coupling of right-handed quarks to W as suggested by certain type of effective electroweak theories.
Clean tests of a small admixture of right-handed quark currents directly coupled to the standard W are still lacking. We show that such non-standard couplings can be significantly constrained measuring the value of the scalar Kpi form factor at the Callan-Treiman point to a few percent. A realistic prospect of such a measurement in K^L_{mu3} decay based on an accurate dispersive representation of the scalar form factor is presented. The inadequacy of the currently used linear parametrisation is explained and illustrated using recent KTeV data. We briefly comment on the charged Kaon mode.
We study contributions of quark-squark-gluino interactions in Minimal Supersymmetric Standard Model (MSSM) to B->PP (PP =Kpi, pipi, KK) decays using QCD improved factorization method for the evaluation of the hadronic matrix elements and taking into account renormalization group running of the Wilson coefficients from SUSY scale (~ m_{\tilde q}) to the low energy scale (= m_b) applicable to B decays. Using the most recent experimental data we obtain constraints on flavor changing Supersymmetric (SUSY) parameters (δ_{ij})_{LL, RR}. For ΔS = -1 processes, b-> s gamma is usually considered to giv…
We derive expressions for strangeness-changing scalar form factors, which incorporate known theoretical constraints both at low and high energies. Their leading behaviour in the limit of a large number of colours is calculated from the resonance chiral Lagrangian. A set of short-distance constraints on the scalar resonance couplings is obtained, imposing the form factors to vanish at infinite momentum transfer. Making use of previous results on S-wave KPi scattering [1], and a coupled--channel dispersion-relation analysis, the KPi, KEta and KEta' scalar form factors are calculated up to 2 GeV.…
We analyze the contributions of hadronic final-state interactions to the strong phases generated in the B -> Kpipi weak decays. To this end, we develop an alternative approach to the commonly employed isobar model based upon scalar and vector form factors for pion-pion and pion-kaon interactions.
The coherence factor and average strong phase difference of D0 and D0bar decay amplitudes to the same final state play an important role in the precision determination of the CKM parameter gamma using B- -> DK- and related decay modes. So far, this important input from the charm sector could only be obtained from measurements based on quantum-correlated DDbar pairs produced at the charm threshold. We propose to constrain these parameters using charm mixing, using the large charm samples available at the B factories and LHCb. We demonstrate for the example of D0->Kpipipi that a substantial impr…
Final-state rescattering effects on the hadronic B decays and their impact on direct CP violation are examined. The phenomenology of the polarization anomaly in $B\toϕK^*$ decays is discussed.
We evaluate the non-resonant decay amplitude of the process $B^\pm\to K^\pmπ^+ π^-$ using an approach based on final state hadronic interactions described in terms of meson exchanges. We conclude that this mechanism generates inhomogeneities in the Dalitz plot of the B decay.
It is shown that the study of the $ω-ρ^0$ interference pattern in the $J/ψ\to (ρ^0+ω)η\toπ^+π^-η$ decay provides the evidence for the large (nearly $90^\circ$) relative phase between the one-photon and the three-gluon decay amplitudes.
We study the final state strong interactions of the $B\rightarrow DK$ decay processes, using the Regge model. We conclude that the final state interaction phases are very small, typically a few degrees. Neglecting final state interactions in obtaining the weak decay amplitudes is a good approximation.
The branching fraction of the psi(3770) decays into charmless final states is estimated in the S- and D-wave charmonia mixing scheme. With the information of the hadronic decays of J/psi and psi(3686), it is found that a large branching fraction, up to 13% of the total psi(3770) decays may go to charmless final states. The experimental search for these decays is also discussed.
Two-body hadronic weak decays of Bc meson involving tensor meson in the final state are studied by using Isgur- Scora-Grinstein-Wise (ISGW II) model. Decay amplitudes are obtained using the factorization scheme in the Spectator Quark Model. Branching ratios for the charm changing and bottom changing decay modes are predicted.
The recent observation of the decay $\ob \to Λ_c^+ \bar p$ suggests that related decays may soon be visible at $e^+ e^-$ colliders. It is shown how these decays can shed light on strong final-state phases and amplitudes involving the spectator quark, both of which are normally expected to be small in B decays.
An attempt is made to identify circumstances under which the weak decays of $D$ and $B$ mesons may display large differences between eigenphases of strong final-state interactions. There are several cases in which rescattering from other final states appears to enhance decay rates with respect to estimates based on the factorization hypothesis.
Hadron resonances affect nonexotic $D^o$ decays but not $B$ decays which are far from the resonance region. We obtain new information from {\bf exclusive} decays and show that interference between colour favoured and colour suppressed diagrams is {\bf constructive} in $B$ and (some) $D$ decays in contrast to the inclusive decays where a net Pauli destructive interference is claimed. We suggest that a systematic study of $B$ decay final states containing excited mesons such as $a_1 D$ or $πD^{**}$ show opposite behaviour for $B^o$ and $B^+$ relative to the ground state channels. We give inequal…
Contrary to wide-spread opinion that the final state interaction (FSI) enhances the amplitude $<2π;I=0|K^0>$, we argue that FSI does not increase the absolute value of this amplitude.
The two-body nonleptonic charmed meson decays into two pseudoscalar mesons are studied using one-particle-exchange method. The effects of the final state interactions are analyzed through the strong phases extracted from the experimental data.
The role of inelastic final-state interactions in CP asymmetries and branching ratios is investigated in certain chosen single isospin two-body hadronic B decays. Treating final-state interactions through Pomeron and Regge exchanges, we demonstrate that inelastic final state interactions could lead to sizeable effects on the CP asymmetry.
We study the role played by the final-state interactions (fsi) in heavy quark decays using Pomeron and Regge exchanges to describe high energy scattering. At center of mass energy $\sqrt{s}\sim 5GeV $, Pomeron dominance does not apply. We study the behavior of the decay amplitudes as $\sqrt{s} $ is varied close to the B mass. We also investigate the behavior of the decay amplitude as $\sqrt{s}\to \infty $. Our conclusion is that the decay amplitudes approach a real value asymptotically.
Final-state rescattering effects on the hadronic B decays and their impact on direct and mixing-induced CP asymmetries are examined. Implications for some phenomenologies are briefly discussed.
The scattering amplitude of D Pi at the energy of the B mass can be calculated using Regge theory. Recent papers have used this to calculate the final state strong phases in the decays B to D Pi. It is argued that while the Regge amplitude can yield an absorption correction to the decay rate, it is not useful for determining the strong phase.
The availability of data on $B_s$ decays to strange quasi-two-body final states, either with or without charmonium opens new possibilities for understanding different contributions of weak diagrams and in particular the relative contributions of tree and penguin diagrams. Corresponding $B_d$ and $B_s$ decays to charge conjugate final states are equal in the SU(3) symmetry limit and the dominant SU(3) breaking mechanism is given by ratios of CKM matrix elements. Final State Interactions effects should be small, because strong interactions conserve $C$ and should tend to cancel in ratios between…
To understand the short-distance vs long-distance final-state interactions, we have performed a detailed amplitude analysis for the two-body decay, J/psi into vector and pseudoscalar mesons. The current data favor a large relative phase nearly 90 degrees between the three-gluon and one-photon decay amplitudes. The source of this phase is apparently in the long-distance final-state interaction. Nothing anomalous is found in the magnitudes of the three-gluon and one-photon amplitudes. We discuss implications of this large relative phase in the weak decay of heavy particles.
We analyze final state strong interaction effects in $B -> D ρ$ and $B -> D^{*}π$ decays using the Regge model. We find that, due to the smallness of the contributions from the non-leading Regge trajectories ($ρ$, $f$, $π$ etc.), final state interaction phases are small if the Pomeron coupling to the charm quark is suppressed in comparison to lighter quarks. Our conclusion is that for $B$ decays into states containing charm, final state interaction effects should play a minor role.
The final state interactions (FSI) in Delta S=-1, Delta C=\pm 1, decays of B-meson are discussed. The rescattering corrections are found to be of order of 15-20%. The strong interaction phase shifts are estimated and their effects on CP-asymmetry are discussed.
The polarization measurement in the inclusive B decay provides us with a simple test of how much the long-distance final-state interaction takes place as the energy of the observed meson varies in the final state. We give the expectation of the perturbative QCD for the energy dependence of the helicity fractions in a semiquantitative form. Experiment will tell us for which decay processes the perturbative calculation should be applicable.
I give a brief review of final state interactions (FSI) in heavy meson decays, paying particular attention to B-meson physics. Available theoretical methods for dealing with the effects of FSI are discussed.
The non-$D \bar D$ decays of the $\ppp = ψ(3770)$ resonance are reviewed and possibilities for further measurements are noted. These decays can shed light on S--D mixing, the ``missing'' $ψ' = ψ(3686)$ decays, a possible discrepancy between the total and $D \bar D$ cross sections at the $\ppp$, and rescattering effects contributing to enhanced $b \to s$ penguin amplitudes in $B$ meson decays.
In this article, we study the final-state rescattering effects in the decay $B^0 \to η_cK^*$, the numerical results indicate the corrections are comparable with the contribution from the naive factorizable amplitude, and the total amplitudes can accommodate the experimental data.
We consider the semileptonic and nonleptonic $D_s$ decay modes to final states with $η$ and $η^\prime$. We use QCD sum rules to determine the $D_s \to η$ form factor $f_+^η$, and a generalized factorization ansatz to compute nonleptonic decays. We propose a parameterization of possible OZI suppressed contributions producing the $η^\prime$ in the final state, compatible with current data; such a scheme can be further constrained improving the precision of the measurement of the $D_s$ decay rates, as expected by the ongoing experiments.
We discuss the rescattering effects in decays $B\to π+K$. The picture we take is very simple: first, B decay into $K*ρ$, then $K*$ and $ρ$ go to kaon and pion by exchanging a pion. We find a up to ten percent CP violation asymmetry rate. We also discuss its correction to the constraint of angle $γ$ proposed recently.
The standard electroweak final-state interaction induces a false T-odd correlation in the top-quark semileptonic decay. The correlation parameter is calculated in the standard model and found to be considerably larger than those that could be produced by genuine T-violation effects in a large class of theoretical models.
The CLEO Collaboration has now observed the decays $B^+ \to ωπ^+$ and $B \to ωK^+$ with branching ratios of $(1.1^{+0.6}_{-0.5} \pm 0.2) \times 10^{-5}$ and $(1.5^{+0.7}_{-0.6} \pm 0.3) \times 10^{-5}$, respectively. These are the first reported decays to charmless final states involving a vector (V) and a pseudoscalar (P) meson. The implications of these decays for others of B mesons to charmless VP final states are explored. In a model-independent approach, using only flavor SU(3) symmetry, several tests are proposed for an anticipated hierarchy among different contributions to decay amplitu…
We study $D \to ππ$ decays with final state interactions considered in one-particle-exchange method. A clear physical picture for final state interactions based on quark and hadronic level diagrams is presented. A strong phase is introduced for hadronic effective couplings, which is crucial for explaining the experimental data of $D^+\to π^+π^0$, $D^0\to π^+π^-$, and $D^0\to π^0π^0$. Rescattering effects between different $D$ decay channels are usually large. They are important for obtaining correct branching ratios for $D\to ππ$ decays in theoretical calculation.
In view of important implications in the B decay, the 0-0- decay modes of J/psi are analyzed with broken flavor SU(3) symmetry in search for long-distance final-state interactions. If we impose one mild theoretical constraint on the electromagnetic form factors, we find that a large phase difference of final-state interactions is strongly favored between the one-photon and the gluon decay amplitudes. Measurement of the π+π- and K+K- cross sections off the J/psi peak in e+e- annihilation can settle the issue without recourse to theory.
We study the final state interaction effects in $B\to KK$ decays. We find that the $t$ channel one-particle-exchange diagrams cannot enhance the branching ratios of $\bar{B^0}\to K^0\bar{K^0}$ and $B^-\to K^0K^-$ very sizably. For the pure annihilation process $\bar{B^0}\to K^+K^-$, the obtained branching ratio by final state interaction is at ${\cal{O}}(10^{-8})$.
We study final-state interactions in nonleptonic weak decays in statistical models by averaging over ensembles of strong interaction S-matrices. The models range from one with completely random strong interactions, which gives extensive mixing between physical states, to models with feeble final-state interactions, characterized by small phase shifts.
We discuss the low-mass enhancement effect in the baryon-antibaryon invariant mass in three-body baryonic B decays using final state interactions in the framework of Regge theory. We show that the rescattering between baryonic pair can reproduce the observed mass spectrum.
A global previous analysis of two-body nonleptonic decays of $D$ mesons has been extended to the decays involving light scalar mesons. The allowance for final state interaction also in nonresonant channels provides a fit of much improved quality and with less symmetry breaking in the axial charges. We give predictions for about 50 decay branching ratios yet to be measured. We also discuss long distance contributions to the difference $ΔΓ$ between the $D_S$ and $D_L$ widths.
In this paper, we investigate phenomenologically two-body weak decays of the bottom mesons emitting pseudoscalar/vector meson and a tensor meson. Form factors are obtained using the improved ISGW II model. Consequently, branching ratios for the CKM-favored and CKM-suppressed decays are calculated.
The final state interactions of pions in decays $K^\pm\toπ^\pmπ^0π^0$ are considered using the methods of quantum mechanics. We show how to incorporate the electromagnetic effects in the amplitudes of these decays and to work out the relevant expressions valid above and below the two charged pions production threshold $M_c=2m$. The electromagnetic corrections are given as evaluated in a potential model.
The kaons decays to the pairs of charged and neutral pions are considered in the framework of the non-relativistic quantum mechanics. The general expressions for the decay amplitudes to the two different channels accounting for the strong interaction between pions are obtained. The developed approach allows one to estimate the contribution of terms of any order in strong interaction and correctly takes into account the electromagnetic interaction between the pions in the final state.
The effects of final state interactions (FSI) in hadronic B-decays are investigated. The model for FSI, based on Regge phenomenology of high-energy hadronic interactions is proposed. It is shown that this model explains the pattern of phases in matrix elements of $B\toππ$ and $B\toρρ$ decays. These phases play an important role for CP-violation in B-decays. The most precise determination of the unitarity triangle angle $α$ from $B_d\to ρπ$ decays is performed. The relation between CP-asymmetries in $B\to Kπ$ decays is discussed. It is emphasized that the large distance FSI can explain the stru…
From an estimate of the meson-meson inelastic scatterin at 5 GeV it is concluded that a typical strong phase in B decays to two mesons is of order of 20 degrees. For a particular final state an estimate of the phase depends on whether that state is more or less probable as a final state compared to those states to which it is connected by the strong interaction S matrix.
I discuss some recent results on the systematic behavior of final state rescattering which makes use of the limit of a heavy B meson. The results suggest that soft final state interactions do not disappear in the large $m_B$ limit. Soft and hard final state phases can both contribute to CP violating asymmetries in B decay. The way that the soft phases occur is interesting theoretically and suggests the violation of local quark-hadron duality.
