Scalar mesons and polarizability of the nucleon
نویسنده
چکیده
It is shown that the scalar mesons σ , f0(980) and a0(980) as t-channel exchanges quantitatively solve the problem of diamagnetism and give an explanation of the large missing part of the electric polarizability α showing up when only the pion cloud is taken into account. The electric polarizability of the proton αp confirms a two-photon width of the σ meson of Γσγγ = (2.58±0.26) keV.
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تاریخ انتشار 2008