We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Lightest scalar resonances and the dynamics of the γγ → ππ reactions.
- Authors
Achasov, N. N.; Shestakov, G. N.
- Abstract
The high-statistics Belle data on the γγ → π+π− and γγ → π0π0 reactions have been jointly analyzed. The main dynamical mechanisms of these reactions for energies below 1.5 GeV have been revealed. It has been shown that the direct coupling constants of the σ(600) and f0(980) resonances with a γγ pair are small and that the σ(600) → γγ and f0(980) → γγ decays are four-quark transitions due primarily to π+π− and K+ K−-loop mechanisms, respectively. The role of the chiral shielding of the σ(600) resonance is emphasized. The widths of the f0(980) → γγ and σ(600) → γγ decays averaged over the resonance mass distributions, as well as the width of the f2(1270) → γγ decay, are estimated as $$ \langle \Gamma _{f_0 \to \gamma \gamma } \rangle _{\pi \pi } \approx 0.19 keV, \langle \Gamma _{\sigma \to \gamma \gamma } \rangle _{\pi \pi } \approx 0.45 keV $$, and $$ \Gamma _{f_2 \to \gamma \gamma } (m_{f_2 }^2 ) \approx 3.8 keV $$.
- Subjects
SCALAR field theory; RESONANCE integral (Nuclear physics); DYNAMICS; COUPLING constants; QUARKS
- Publication
JETP Letters, 2008, Vol 88, Issue 5, p295
- ISSN
0021-3640
- Publication type
Article
- DOI
10.1134/S0021364008170025