0000000000255764
AUTHOR
H. C. Chiang
Unitary chiral dynamics in decays and the role of scalar mesons
We make a theoretical study of the J/psi decays into omegapipi, phipipi, omegaK (K) over bar and phiK (K) over bar using the techniques of the chiral unitary approach stressing the important role of the scalar resonances dynamically generated through the final state interaction of the two pseudoscalar mesons. We also discuss the importance of new mechanisms with intermediate exchange of vector and axial-vector mesons and the role played by the OZI rule in the J/ psi phipipi vertex, quantifying its effects. The results nicely reproduce the experimental data for the invariant mass distributions in all the channels considered. (C) 2004 Elsevier B.V. All rights reserved.
Unitary chiral dynamics in J/Psi decays into VPP and the role of the scalar mesons
We make a theoretical study of the $\J$ decays into $\omega\pi\pi$, $\phi\pi\pi$, $\omega K \bar{K}$ and $\phi K\bar{K}$ using the techniques of the chiral unitary approach stressing the important role of the scalar resonances dynamically generated through the final state interaction of the two pseudoscalar mesons. We also discuss the importance of new mechanisms with intermediate exchange of vector and axial-vector mesons and the role played by the OZI rule in the $\J\phi\pi\pi$ vertex, quantifying its effects. The results nicely reproduce the experimental data for the invariant mass distributions in all the channels considered.
BACKGROUND FOR (μ-, e-) CONVERSION IN NUCLEI FROM MUON DECAY IN ORBIT
A reanalysis of the problem of μ- decay in orbit is done in order to estimate backgrounds for (μ-, e-) conversion. Some approximations are done in order to obtain a very simple formula for the decay rate close to the maximum electron energy. Comparison with more sophisticated approaches leads to differences in the results which cannot be easily interpreted in terms of the approximations which has been done so far. In view of the relevance of this reaction in the planning of (μ-, e-) conversion experiments we point out at the convenience of some independent accurate evaluation.
Inclusive muon capture in light nuclei
We study total muon capture rates in light nuclei, taking into account renormalizations of the nuclear vector and axial vector strengths. We estimate the influence in the results of uncertainties of the spin-isospin interaction parameter and nuclear densities. A few of these reactions are theoretical benchmarks for physics involving searches for neutrino oscillations. New experiments in muon capture in several targets are suggested, in the light of some discrepancies with theory, crudeness of some experimental results and relevance to neutrino physics.