Quarkonium chromo - polarizability from the decays
نویسنده
چکیده
It is pointed out that the diagonal amplitude of the E1 − E1 chromo-electric interaction with soft gluon fields (chromo-polarizability) can be measured directly for the J/ψ and Υ resonances in the decays J/ψ → ππℓ + ℓ − and Υ → ππℓ + ℓ − with soft pions. For the J/ψ this amplitude is often discussed in connection with the J/ψ interaction with nuclear matter, while for the Υ the chromo-polarizability enters the estimates of the non-perturbative mass shift of the resonance relevant to precision determination of the b quark mass from the Υ mass.
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