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arXiv · 0809.2475

Obtaining sigma --> gamma gamma Width from Nucleon Polarizabilities

Joaquim Prades·Jose Bernabeu
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Abstract

We propose a new method that fixes the coupling to two photons of the recently found lightest QCD resonance, the sigma. This coupling provides crucial information for discriminating the yet unknown nature of this special state. Our method uses available data on the nucleon polarizabilities together with analyticity and unitarity. Taking into account all the uncertainties, our result is Gamma_{pole}= 1.2 +- 0.4 keV.

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Joaquim Prades, Jose Bernabeu. 2008-09-15. Obtaining sigma --> gamma gamma Width from Nucleon Polarizabilities. https://doi.org/10.1016/j.nuclphysbps.2008.12.062

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