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arXiv · 1706.09502

Light Meson Masses using AdS/QCD modified Soft Wall Model

Abstract

We analyze light vector and scalar meson mass spectra using a novel approach where a modified soft wall model with a UV-cutoff is considered. Including this cutoff introduces an extra energy scale. For this model, we found that the masses for the scalar and vector spectra are well fitted within a very small RMS error for 14 of these states, with non-linear trajectories given by two common parameters, the UV locus $z_0$ and the quadratic dilaton profile slope $\kappa$. We concluded that in this model the $f_{0}(500)$ scalar resonance cannot be fitted holographycally as a $q\overline{q}$ state since we could not find a trajectory that included this pole. This result is in agreement with the most recent phenomenological and theoretical methods.

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Santiago Cortés, Miguel Ángel Martín Contreras, José Rolando Roldán. 2017-06-28. Light Meson Masses using AdS/QCD modified Soft Wall Model. https://doi.org/10.1103/physrevd.96.106002

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