A helpful analogy between the covalent bond and particle spectroscopy

D V Bugg (1)

1 QMUL - Queen Mary University of London

It is proposed that meson resonances are linear combinations of q ? q and meson-meson (MM)) baryon resonances are combinations of qqq and meson-baryon (MB). Mixing between these combinations arises via decays of connned states to meson-meson or meson-baryon. There is a precise analogy with the covalent bond in molecular physicss it helps to visualise what is happening physically. One eigenstate is lowered by the mixingg 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. The overall pattern of light mesons is consistent with nearly linear Regge trajectories, hence q ? q component s. T h e r e i s n o o b vious reason why this pattern should arise from dynamically generated states without q ? q content.

Mots clés: 12.39.Ki; 12.40.Yx; 13.25.Ft; 14.20.Gk

D V Bugg. A helpful analogy between the covalent bond and particle spectroscopy. Journal of Physics G: Nuclear and Particle Physics, 2010, 37 (5), pp.55002. ⟨10.1088/0954-3899/37/5/055002⟩. ⟨hal-00630014⟩