Speaker
Mr
Jorge Segovia
(University of Salamanca)
Description
Meson strong decay is a complex non-perturbative process that has not been described from QCD first principles yet. Instead, several phenomenological models have been developed to deal with this topic, being the 3P0 [1], the flux-tube [2] and the Cornell [3, 4] models the most popular.
To address a more fundamental description of the decay mechanism, one has to describe hadron strong decays in terms of quark and gluon degrees of freedom. However, there has been little previous work in this area. Two different examples are the study of open-charm decays of charmonium resonances by Eichten et al. [3], who assumed that decays are due to pair production from the static part of a Lorentz vector confining interaction, and the study of a few strong decays in the light sector by Ackleh et al. [4], who assumed that the quark-antiquark pair production comes from one-gluon exchange and a scalar confining interaction.
Following Ref. [4] for the development of a microscopic model, the strong decays are driven by the same interquark Hamiltonian which determines the spectrum given by the one-gluon exchange and the confining interaction. These interactions and their associated decay amplitudes are undoubtedly all present and should be added coherently.
Our constituent quark model (CQM) [5] for the heavy quark sector has a one-gluon exchange term and a mixture of Lorentz scalar and vector confining interactions. This completely defines our microscopic model for strong decays. Unlike previous works we use a screening confinement interaction and also a mixture between scalar and vector Lorentz structures, which is already fixed. The wave functions for the mesons involved in the reactions are the solutions of the Schrödinger equation.
Our results are in reasonable agreement with the predictions obtained by a 3P0 model. We obtain a total decay width of 19 MeV for the psi(3770) resonance in a parameter free calculation which agrees with the experimental data. Other decays of charmonium states will be presented.
[1] L. Micu, Nucl. Phys. B 10, 521 (1969).
[2] R. Kokoski and N. Isgur, Phys. Rev. D 35, 907 (1987).
[3] E. Eichten, K. Gottfried, T. Kinoshita, K.D. Lane and T.
M. Yan, Phys. Rev. D 17, 3090 (1978); 21, 203 (1980).
[4] E.S. Ackleh, T. Barnes and E.S. Swanson, Phys. Rev. D 54, 6811 (1996).
[5] J. Vijande, F. Fernandez and A. Valcarce, J. Phys. G 31, 481 (2005).
[6] J. Segovia, A.M. Yasser, D.R. Entem and F. Fernandez, Phys. Rev. D 78, 114033 (2008).
Primary authors
Prof.
David R. Entem
(University of Salamanca)
Prof.
Francisco Fernandez
(University of Salamanca)
Mr
Jorge Segovia
(University of Salamanca)
