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arXiv · 0708.1405

Determination of the magnetic susceptibility of the quark condensate using radiative heavy meson decays

J. Rohrwild
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Abstract

We use a light-cone sum rule (LCSR) analysis of the branching ratios of radiative meson decays to contrain the value of the magnetic susceptibility of the quark condensate $χ(μ)$. For the first time, we use a complete set of three-particle distribution amplitudes that enables us to give a consistent prediction for the branching ratios. Furthermore we will make use of a very recent update of several non-perturbative parameters. Our final result for $χ(μ= 1 {\rm GeV})= 2.85 \pm 0.5 {\rm GeV}^{-2}$ (assuming asymptotic wave functions) agrees with the currently used value of $3.15 \pm 0.3 {\rm GeV}^{-2}$.

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J. Rohrwild. 2007-08-23. Determination of the magnetic susceptibility of the quark condensate using radiative heavy meson decays. https://doi.org/10.1088/1126-6708%2F2007%2F09%2F073

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