Abstract
The γ* → γf2(1270) and γ* → γa2(1320) transition form factors are considered up to high energies, along with the cross sections for the respective processes e+e− → γ* → f2γ and e+e− → γ* → a2γ. It is shown that QCD asymptotic behavior of the amplitudes for the reactions e+e− → γ* → f2γ and e+e− → γ* → a2γ can be reached after the compensation of the contributions of the ρ(770) and ω(782) mesons with the contributions of their radial excitations. The ratio σ(e+e− → γ* → f2γ)/σ(e+e− → γ* → a2γ) ≈ 25/9, obtained on the basis of the two-quark model of a2 and f2 and within QCD, is used to determine σ(e+e− → γ* → a2γ) at high energies. Recent data from the Belle detector on the γ*(Q2)γ → f2 transition over the region extending up to Q2 = 30 GeV2 are taken into account. A substantial improvement of experimental accuracies is required for a detailed comparison of our predictions with experimental data at high energies. A recent measurement of the e+e− → f2γ → π+π−γ cross section at 10.58 GeV with the BaBar detector gives grounds to hope for this.
Similar content being viewed by others
References
BaBar Collab. ( B. Aubert et al.), Phys. Rev. D 80, 052002 (2009)
P. del Amo Sanchez et al., Phys. Rev. D 84, 052001 (2011)
Belle Collab. ( S. Uehara et al.), Phys. Rev. D 86, 092007 (2012).
N. N. Achasov, A. V. Kiselev, and G. N. Shestakov, Phys. At. Nucl. 79, 397 (2016); arXiv: 1504.07346.
Belle Collab. ( M. Masuda et al.), Phys. Rev. D 93, 032003 (2016), arXiv: 1508.06757.
N. N. Achasov, A. V. Kiselev, and G. N. Shestakov, JETP Lett. 102, 571 (2015); arXiv: 1509.09150.
N. N. Achasov and A. V. Kiselev, EPJWeb Conf. 125, 04003 (2016).
V. M. Braun, N. Kivel, M. Strohmaier, and A. A. Vladimirov, J. High Energy. Phys. 1606, 39 (2016); arXiv: 1603.09154.
BaBar Collab. ( J. P. Lees et al.), Phys. Rev. D 92, 072015 (2015).
N. N. Achasov, A. I. Goncharenko, A. V. Kiselev, and E. V. Rogozina, Phys. Rev. D 88, 114001 (2013); Phys. Rev. D 89 059906 (E) (2014).
N. N. Achasov and V. A. Karnakov, Z. Phys. C30, 141 (1986).
Particle Data Group ( K. A. Olive et al.), Chin. Phys. C 38, 090001 (2014).
N. N. Achasov and A. A. Kozhevnikov, Phys. Rev. D 55, 2663 (1997); Phys. Rev. D 57, 4334 (1998).
V. L. Chernyak and A. R. Zhitnitsky, Phys. Rep. 112, 173 (1984).
V. N. Baier and A. G. Grozin, Sov. J. Part. Nucl. 16, 1 (1985).
P. Kroll, Eur.Phys. J. C 77, 95 (2017).
M. Diehl, T. Gousset, and B. Pire, Phys. Rev. D 62, 073014 (2000).
E. Witten, Nucl. Phys. B 160, 57 (1979).
S. S. Afonin, Phys. Lett. B 576, 122 (2003).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © N.N. Achasov, A.V. Kiselev, 2018, published in Yadernaya Fizika, 2018, Vol. 81, No. 1, pp. 32–39.
Rights and permissions
About this article
Cite this article
Achasov, N.N., Kiselev, A.V. γ* → γf2(1270) and γ* → γa2(1320) Transition Form Factors in e+e− Collisions. Phys. Atom. Nuclei 81, 43–50 (2018). https://doi.org/10.1134/S1063778818010027
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1063778818010027