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arXiv · hep-ex/0302004

Experimental study of the e+e- -> pi0 gamma process in the energy region sqrt(s)=0.60-0.97 GeV

M. N. Achasov·K. I. Beloborodov·A. V. Berdugin·A. G. Bogdanchikov·A. V. Bozhenok·A. D. Bukin·D. A. Bukin·T. V. Dimova·V. P. Druzhinin·V. B. Golubev·V. N. Ivanchenko·A. A. Korol·S. V. Koshuba·E. V. Pakhtusova·A. A. Polunin·E. E. Pyata·A. A. Salnikov·S. I. Serednyakov·V. V. Shary·Yu. M. Shatunov·V. A. Sidorov·Z. K. Silagadze·A. N. Skrinsky·A. G. Skripkin·Yu. V. Usov·A. A. Valishev·A. V. Vasiljev
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Abstract

Results of the study of the e+e-->pi0 gamma process with SND detector at VEPP-2M collider in the c.m.s. energy range sqrt(s)=0.60-0.97 GeV are presented. Using 36513 selected events corresponding to a total integrated luminosity of 3.4 pb^-1 the e+e-->pi0 gamma cross section was measured. The energy dependence of the cross section was analyzed in the framework of the vector meson dominance model. The data are well described by a sum of phi,omega,rho0->pi0 gamma decay contributions with measured decay probabilities: Br(omega->pi0 gamma)=(9.34+-0.15+-0.31)% and Br(rho0->pi0 gamma)=(5.15+-1.16+-0.73)*10^-4 . The rho-omega relative interference phase is phi(rho,omega}=(-10.2+-6.5+-2.5) degree.

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M. N. Achasov, K. I. Beloborodov, A. V. Berdugin, A. G. Bogdanchikov, A. V. Bozhenok, A. D. Bukin, D. A. Bukin, T. V. Dimova, V. P. Druzhinin, V. B. Golubev, V. N. Ivanchenko, A. A. Korol, S. V. Koshuba, E. V. Pakhtusova, A. A. Polunin, E. E. Pyata, A. A. Salnikov, S. I. Serednyakov, V. V. Shary, Yu. M. Shatunov, V. A. Sidorov, Z. K. Silagadze, A. N. Skrinsky, A. G. Skripkin, Yu. V. Usov, A. A. Valishev, A. V. Vasiljev. 2003-02-05. Experimental study of the e+e- -> pi0 gamma process in the energy region sqrt(s)=0.60-0.97 GeV. https://doi.org/10.1016/s0370-2693(03)00336-8

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