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arXiv · 0712.3036

Quenched mesonic spectrum at large N

Luigi Del Debbio·Biagio Lucini·Agostino Patella·Claudio Pica
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Abstract

We compute the masses of the $π$ and of the $ρ$ mesons in the quenched approximation on a lattice with fixed lattice spacing $a \simeq 0.145 \ \mathrm{fm}$ for SU($N$) gauge theory with $N = 2,3,4,6$. We find that a simple linear expression in $1/N^2$ correctly captures the features of the lowest-lying meson states at those values of $N$. This enables us to extrapolate to $N = \infty$ the behaviour of $m_π$ as a function of the quark mass and of $m_ρ$ as a function of $m_π$. Our results for the latter agree within 5% with recent predictions obtained in the AdS/CFT framework.

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Luigi Del Debbio, Biagio Lucini, Agostino Patella, Claudio Pica. 2008-03-16. Quenched mesonic spectrum at large N. https://doi.org/10.1088/1126-6708%2F2008%2F03%2F062

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