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arXiv · 0710.1790

Static and dynamic properties of hadronic systems with heavy quarks b and c

Abstract

This thesis has been devoted to the study of different properties of hadrons with one and two heavy quarks $c$ and/or $b$. All calculations have been done in the framework of a nonrelativistic constituent quark model. In order to check the sensitivity of our results to the inter--quark interaction we have used five different quark--quark potentials. The spread in results gives an estimation of theoretical uncertainties and so has been quoted. Most observables studied change only at the level of a few per cent when changing the interaction potential. Another source of theoretical uncertainty is the use of nonrelativistic kinematics in the evaluation of the orbital wave functions and the construction of our nonrelativistic states, although we think that a good part of these relativistic effects are contained in an effective way in the parameters of the quark-quark potentials, which were adjusted in the original works to reproduce the experimental spectra of mesons. Mesons wave functions have been evaluated using a Numerov algorithm, while for baryons the three body problem has been solved using a variational approach with ansatz wave functions that include simplifications that arise from HQS and HQSS. To compute hadron decays we have relied on the impulse approximation, which induces small axial and vector current conservation violations due to binding effects. These binding effects, though they affect some of the weak form factors analyzed, have little influence on the decay widths.

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BibTeXRIS

J. M. Verde-Velasco. 2007-10-09. Static and dynamic properties of hadronic systems with heavy quarks b and c. https://arxiv.org/abs/0710.1790

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