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arXiv · 1509.09150

Study of the $f_2(1270)$ and $a_2(1320)$ resonances in $γ^*(Q^2)γ$ collisions

N. N. Achasov·A. V. Kiselev·G. N. Shestakov
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Abstract

We discuss studies of the $Q^2$ dependence of the $f_2(1270)$ and $a_2 (1320)$ production cross sections in $γ^*(Q^2)γ$ collisions at current and coming into operation colliders with a high luminosity. Changing the dominant helicity amplitude occurs in the reactions $γ^*(Q ^2)γ\to f_2(1270)$ and $γ^*(Q^2) γ\to a_2(1320)$ with increasing $Q^2$. This is caused by the coming of the QCD asymptotics. It is shown that the transition to the asymptotic behavior of QCD in the amplitudes $γ^*(Q^2) γ\to f_2(1270),a_2(1320)$ is provided by the compensation of the contributions of ground vector states $ρ$ and $ω$ in $Q^2$-channel with the contributions of their radial excitations.

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N. N. Achasov, A. V. Kiselev, G. N. Shestakov. 2015-12-09. Study of the $f_2(1270)$ and $a_2(1320)$ resonances in $γ^*(Q^2)γ$ collisions. https://doi.org/10.1134/s002136401521002x

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