Can experiment distinguish tetraquark scalars, molecules and $\qq$ mesons?

Abstract

Scalar mesons are a key expression of the strong coupling regime of QCD. How those with $I_3=0$ couple to two photons supplies important information about which is transiently $\bar{q}q$ or $\overline{qq}qq$ or multi-meson molecule or largely glue, provided (i) we know the location of the corresponding poles in the complex energy plane, and (ii) we have reliable predictions from strong coupling QCD of the radiative widths for these compositions. Number (i) is being supplied by careful analyses of high statistics data particularly that coming from $B$, $D$, $J/\psi$ and $\varphi$ decays. Number (ii) is still required, before we can answer the question in the title.

arXiv comment16 pages, 6 figures Invited talk at the Yukawa International Seminars (YKIS) 2006 "New Frontiers in QCD: Exotic Hadrons & Hadronic Matter", Nov.-Dec. 2006

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• A new look at scalar mesons
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Cited by in corpus (9)

• Physics with the KLOE-2 experiment at the upgraded DA$\varphi$NE
• The Scalar Meson f0(980) in Heavy-Meson Decays
• Distinguishing two kinds of scalar mesons from heavy meson decays
• A Dispersive Analysis on the $f_0(600)$ and $f_0(980)$ Resonances in $\gamma \gamma \to {\pi }^{+}{\pi }^{-},{\pi }^0{\pi }^0$ Processes
• On the two-photon decay width of the sigma meson
• Relating multichannel scattering and production amplitudes in a microscopic OZI-based model
• How tetraquarks can generate a second chiral phase transition
• KKbar molecules with momentum-dependent interactions
• New physics in B_s^0 -> J/ψϕdecays?