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arXiv · 1806.07609

Search for the process $\mathbf{e^+e^- \to\eta}$

M. N. Achasov·A. Yu. Barnyakov·K. I. Beloborodov·A. V. Berdyugin·D. E. Berkaev·A. G. Bogdanchikov·A. A. Botov·T. V. Dimova·V. P. Druzhinin·V. B. Golubev·L. V. Kardapoltsev·A. S. Kasaev·A. G. Kharlamov·I. A. Koop·L. A. Korneev·A. A. Korol·D. P. Kovrizhin·S. V. Koshuba·A. S. Kupich·R. A. Litvinov·K. A. Martin·N. A. Melnikova·N. Yu. Muchnoi·A. E. Obrazovsky·E. V. Pakhtusova·K. V. Pugachev·Yu. A. Rogovsky·A. I. Senchenko·S. I. Serednyakov·Z. K. Silagadze·D. N. Shatilov·Yu. M. Shatunov·D. A. Shtol·D. B. Shwartz·I. K. Surin·Yu. V. Usov·A. V. Vasiljev·V. N. Zhabin·V. V. Zhulanov
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Abstract

A search for the rare decay $\eta \rightarrow e^+e^-$ is performed using the inverse process $e^+e^- \rightarrow \eta$ in the decay mode $\eta\to\pi^0\pi^0\pi^0 $. We analyze data with an integrated luminosity of 654 nb$^{-1} $ accumulated at the VEPP-2000 $e^+e^-$ collider with the SND detector at the center-of-mass energy $E=m_\eta c ^2\approx 548 $ MeV, and set the upper limit $ {\cal B} (\eta \rightarrow e^+ e^-) < 7 \times 10^{-7} $ at the 90\% confidence level.

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M. N. Achasov, A. Yu. Barnyakov, K. I. Beloborodov, A. V. Berdyugin, D. E. Berkaev, A. G. Bogdanchikov, A. A. Botov, T. V. Dimova, V. P. Druzhinin, V. B. Golubev, L. V. Kardapoltsev, A. S. Kasaev, A. G. Kharlamov, I. A. Koop, L. A. Korneev, A. A. Korol, D. P. Kovrizhin, S. V. Koshuba, A. S. Kupich, R. A. Litvinov, K. A. Martin, N. A. Melnikova, N. Yu. Muchnoi, A. E. Obrazovsky, E. V. Pakhtusova, K. V. Pugachev, Yu. A. Rogovsky, A. I. Senchenko, S. I. Serednyakov, Z. K. Silagadze, D. N. Shatilov, Yu. M. Shatunov, D. A. Shtol, D. B. Shwartz, I. K. Surin, Yu. V. Usov, A. V. Vasiljev, V. N. Zhabin, V. V. Zhulanov. 2018-06-20. Search for the process $\mathbf{e^+e^- \to\eta}$. https://doi.org/10.1103/physrevd.98.052007

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