171 research outputs found
On the eta(b) => J/psi J/psi decay
It has been argued long ago that eta(b) could be observed through the eta(b)
=> J/psi(=> mu+ mu-) J/psi(=> mu+ mu-) decay chain. Recent calculations
indicate that the width of eta(b) into two J/psi is almost three order of
magnitude smaller than the one into the D D*. We study the effects of final
state interactions due to the D D* intermediate state on the J/psi J/psi final
state. We find that the inclusion of this contribution may enhance the short
distance branching ratio of about two orders of magnitude.Comment: LaTeX, 5 pages, 2 figures. Contributed to QCD @ Work 2007:
International Workshop on Quantum Chromodynamics Theory and Experiment,
Martina Franca, Valle d'Itria, Italy, 16-20 Jun 200
Non-Leptonic Two-Body Weak Decays of Charmed Mesons and CP-Violating Asymmetries
The non-leptonic two body decays of D mesons are studied in the framework of
an improved factorization approximation. The final state interaction effects
are taken into account assuming them dominated by nearby resonances. The
agreement with experimental data is quite good. CP-violating asymmetries are
predicted.Comment: 5 pages, LaTeX file. Talk given at 3rd German-Russian Workshop on
Progress in Heavy Quark Physics, Dubna, Russia, 20-22 May 199
Final state interaction effects on the eta(b) => J/psi J/psi decay
We study the effects of final state interactions on the eta(b) => J/psi J/psi
decay. In particular, we discuss the effects of the annihilation of eta(b) into
two charmed meson and their rescattering into J/psi J/psi. We find that the
inclusion of this contribution may enhance the short-distance branching ratio
up to about 2 orders of magnitude.Comment: Parallel talk at ICHEP08, Philadelphia, USA, July 2008. 3 pages,
LaTeX, 3 eps figure
A Geometric Picture For Fermion Masses
We describe a geometric picture for the pattern of fermion masses of the
three generations which is invariant with respect to the renormalization group
below the electroweak scale. Moreover, we predict the upper limit for the ratio
between the Dirac masses of the and neutrinos, .Comment: 7 pages LATEX + 1 figur
Long distance contributions to the eta_b => Jpsi Jpsi decay
It was argued long ago that eta_b could be observed through the eta_b =>
Jpsi(=> mu+ mu-) Jpsi(=> mu+ mu-) decay chain. Recent calculations indicate
that the width of eta_b into two Jpsi is almost 3 orders of magnitude smaller
than the one into the D bar D*. We study the effects of final-state
interactions due to the D bar D* intermediate state on the Jpsi Jpsi final
state. We find that the inclusion of this contribution may enhance the
short-distance branching ratio up to about 2 orders of magnitude.Comment: 4 pages, 3 figures. The estimate of the dispersive contribution was
added. Typos corrected. To be published in Phys. Rev.
Non-Leptonic Two-Body Decays of Charmed Mesons and CP Violation
The nonleptonic two body decays of the and mesons represent a key subject to study possible effects of CP violation. The attention for these decay modes was triggered four years ago by the results of measurements of the difference between CP asymmetries in charged and final state, . Although the measured is now compatible with zero the nonleptonic decays of charmed mesons into a pair of light mesons is an interesting subject for many reasons. Here we discuss phenomenological models to study the decays into two pseudoscalar mesons
On Breaking through Final State Interactions and CP Asymmetries in Decays
We analyse decays to two pseudoscalars assuming the dominant
source of breaking lies in final state interactions. We
obtain an excellent agreement with experimental data and are able to predict CP
violation in several channels based on current data on branching ratios and
. We also make predictions for and the
branching fraction for the decay .Comment: 21 pages. Updated with the 2019 measurement of from LHC
Semileptonic and nonleptonic decays of Bc
Using our relativistic constituent quark model we present results on the
exclusive nonleptonic and semileptonic decays of the Bc-meson. The nonleptonic
decays are studied in the framework of the factorization approximation. We
calculate the branching ratios for a large set of exclusive nonleptonic and
semileptonic decays of the Bc-meson and compare our results with the results of
other models.Comment: 4 pages, proceeding of the talk given by Pietro Santorelli at IFAE
2006, Pavia, 19-21 Aprile 200
J/\psi dissociation cross sections in a relativistic quark model
We calculate the amplitudes and the cross sections of the charm dissociation
processes J/\psi \pi => D \bar D, D* \bar D, D \bar D*, D* \bar D* within a
relativistic constituent quark model. We consistently account for the
contributions coming from both the box and triangle diagrams that contribute to
the dissociation processes. The cross section is dominated by the D* \bar D and
D* \bar D* channels. When summing up the four channels we find a maximum total
cross section of about 2.3 mb at sqrt(s) \approx 4.1 GeV. We compare our
results to the results of other model calculations.Comment: 22 pages, 9 figures, typos corrected, this version will appear on
Phys. Rev.
- …