Measurement of the $$e^+e^- \rightarrow K^+ K^- \pi ^0$$ e + e - → K + K - π 0 cross section with the SND detector

• Main Authors: M. N. Achasov, A. Yu. Barnyakov, M. Yu. Barnyakov, A. A. Baykov, K. I. Beloborodov, A. V. Berdyugin, D. E. Berkaev, A. G. Bogdanchikov, A. A. Botov, A. R. Buzykaev, T. V. Dimova, V. P. Druzhinin, V. B. Golubev, L. V. Kardapoltsev, A. G. Kharlamov, A. A. Korol, D. P. Kovrizhin, E. A. Kravchenko, A. S. Kupich, A. P. Lysenko, K. A. Martin, N. Yu. Muchnoy, N. A. Melnikova, A. E. Obrazovsky, A. P. Onuchin, E. V. Pakhtusova, E. A. Perevedentsev, K. V. Pugachev, Y. S. Savchenko, S. I. Serednyakov, P. Yu. Shatunov, Yu. M. Shatunov, D. A. Shtol, D. B. Shwartz, Z. K. Silagadze, I. K. Surin, Yu. A. Tikhonov, Yu. V. Usov, I. M. Zemlyansky, V. N. Zhabin, V. V. Zhulanov
• Format: Article
• Language: English
• Published: SpringerOpen 2020-12-01
• Series: European Physical Journal C: Particles and Fields
• Online Access: https://doi.org/10.1140/epjc/s10052-020-08719-9
• ISSN: 1434-6044; 1434-6052

Abstract The process $$e^+e^-\rightarrow K^+K^-\pi ^0$$ e + e - → K + K - π 0 is studied with the SND detector at the VEPP-2000 $$e^+e^-$$ e + e - collider. Basing on data with an integrated luminosity of 26.4  $$\hbox {pb}^{-1}$$ pb - 1 we measure the $$e^+e^-\rightarrow K^+K^-\pi ^0$$ e + e - → K + K - π 0 cross section in the center-of-mass energy range from 1.28 up to 2 GeV. The measured mass spectrum of the $$K\pi $$ K π system indicates that the dominant mechanism of this reaction is the transition through the $$K^{*}(892)K$$ K ∗ ( 892 ) K intermediate state. The cross section for the $$\phi \pi ^0$$ ϕ π 0 intermediate state is measured separately. The SND results are consistent with previous measurements in the BABAR experiment and have comparable accuracy. We study the effect of the interference between the $$\phi \pi ^0$$ ϕ π 0 and $$K^*K$$ K ∗ K amplitudes. It is found that the interference gives sizable contribution to the measured $$e^+e^- \rightarrow \phi \pi ^0\rightarrow K^+K^-\pi ^0$$ e + e - → ϕ π 0 → K + K - π 0 cross section below 1.7 GeV.