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arXiv · 1001.1712

The covalent bond in Particle Spectroscopy

D. V. Bugg
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Abstract

It is proposed that meson resonances are linear combinations of q-qbar and meson-meson (MM); baryon resonances are combinations of qqq and meson-baryon (MB). Mixing between these combinations arises via decays of confined states to meson-meson or meson-baryon. There is a precise analogy with the covalent bond in molecular physics; it helps to visualise what is happening physically. One eigenstate is lowered by the mixing; the other moves up and normally increases in width. Cusps arise at thresholds. At sharp thresholds due to S-wave 2-particle decays, these cusps play a conspicuous role in many sets of data.

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D. V. Bugg. 2010-01-11. The covalent bond in Particle Spectroscopy. https://doi.org/10.1063/1.3483338

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