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arXiv · 0804.2710

Holographic QCD beyond the leading order

Youngman Kim·P. Ko·Xiao-Hong Wu
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Abstract

We consider a holographic QCD model for light mesons beyond the leading order in the context of 5-dim gauged linear sigma model on the interval in the AdS$_5$ space. We include two dimension-6 operators in addition to the canonical bulk kinetic terms, and study chiral dynamics of $π$, $ρ$, $a_1$ and some of their KK modes. As novel features of dim-6 operators, we get non-vanishing Br$(a_1 \to πγ)$, the electromagnetic form factor and the charge radius of a charged pion, which improve the leading order results significantly and agree well with the experimental results.

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Youngman Kim, P. Ko, Xiao-Hong Wu. 2008-06-12. Holographic QCD beyond the leading order. https://doi.org/10.1088/1126-6708%2F2008%2F06%2F094

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