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Holographic QCD beyond the leading order

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 نشر من قبل Xiao-Hong Wu
 تاريخ النشر 2008
  مجال البحث
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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 $pi$, $rho$, $a_1$ and some of their KK modes. As novel features of dim-6 operators, we get non-vanishing Br$(a_1 to pi gamma)$, 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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