We evaluate the non-resonant decay amplitude of the process B±→K±π+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.
We derive a simple expression for the production amplitude of two pseudoscalar mesons involving a single scalar resonance. This amplitude is determined by a combination of Watson's phase d(s) and ...another phase o(s), related to an unambiguous two-meson propagator. With a lagrangian model, we study the spp system.
Dispersive representations of the
K
π
vector and scalar form factors are used to fit the spectrum of τ →
K
πν
τ
obtained by the Belle collaboration incorporating constraints from results for
K
l
3
...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 ± 0.31) × 10
−3
and λ″
+
= (12.22 ± 0.14) × 10
−4
. From the pole position on the second Riemann sheet the mass and width of the
K
*(892)
±
are found to be
m
K
*
(892)
±
= 892.0 ± 0.5MeV and Γ
K
*
(892)
±
= 46.5 ± 1.1MeV. The phase-space integrals needed for
K
l
3
decays are calculated as well. Furthermore, the
K
π
isospin-1/2
P
-wave threshold parameters are derived from the phase of the vector form factor. For the scattering length and the effective range we find respectively
a
1
1/2
= (0.166 ± 0.004)
m
π
−3
and
b
1
1/2
= (0.258 ± 0.009)
m
π
−5
.
We introduce parametrizations of hadronic three-body B and D weak decay amplitudes that can be readily implemented in experimental analyses and are a sound alternative to the simplistic and widely ...used sum of Breit-Wigner type amplitudes, also known as the isobar model. These parametrizations can be particularly useful in the interpretation of CP asymmetries in the Dalitz plots. They are derived from previous calculations based on a quasi-two-body factorization approach in which two-body hadronic final-state interactions are fully taken into account in terms of unitary S- and P-wave ππ, πK, and KK¯ form factors. These form factors can be determined rigorously, fulfilling fundamental properties of quantum field-theory amplitudes such as analyticity and unitarity, and are in agreement with the low-energy behavior predicted by effective theories of QCD. They are derived from sets of coupled-channel equations using T-matrix elements constrained by experimental meson-meson phase shifts and inelasticities, chiral symmetry, and asymptotic QCD. We provide explicit amplitude expressions for the decays B±→π+π−π±, B→Kπ+π−, B±→K+K−K±, D+→π−π+π+, D+→K−π+π+, and D0→KS0π+π−, for which we have shown in previous studies that this approach is phenomenologically successful; in addition, we provide expressions for the D0→KS0K+K− decay. Other three-body hadronic channels can be parametrized likewise.
Investigation at a φ-factory can shed light on several debated issues in particle physics. We discuss: (i) recent theoretical development and experimental progress in kaon physics relevant for the ...Standard Model tests in the flavor sector, (ii) the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled-kaon states, (iii) the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and η/ η' mesons, (iv) the contribution to understand the nature of light scalar mesons, and (v) the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We also report on the e + e - physics in the continuum with the measurements of (multi)hadronic cross sections and the study of γ γ processes.
Investigation at a h-factory can shed light on several debated issues in particle physics. We discuss: (i) recent theoretical development and experimental progress in kaon physics relevant for the ...Standard Model tests in the flavor sector, (ii) the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled-kaon states, (iii) the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and /' mesons, (iv) the contribution to understand the nature of light scalar mesons, and (v) the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We also report on the e super(+) e super(− ) physics in the continuum with the measurements of (multi)hadronic cross sections and the study of g g processes.
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