e-Article
Measurement of the $e^+e^-\to\pi^+\pi^-$ cross section from threshold to 1.2 GeV with the CMD-3 detector
Document Type
Working Paper
Author
Collaboration, CMD-3; Ignatov, F. V.; Akhmetshin, R. R.; Amirkhanov, A. N.; Anisenkov, A. V.; Aulchenko, V. M.; Bashtovoy, N. S.; Berkaev, D. E.; Bondar, A. E.; Bragin, A. V.; Eidelman, S. I.; Epifanov, D. A.; Epshteyn, L. B.; Erofeev, A. L.; Fedotovich, G. V.; Gorkovenko, A. O.; Grancagnolo, F. J.; Grebenuk, A. A.; Gribanov, S. S.; Grigoriev, D. N.; Ivanov, V. L.; Karpov, S. V.; Kasaev, A. S.; Kazanin, V. F.; Khazin, B. I.; Kirpotin, A. N.; Koop, I. A.; Korobov, A. A.; Kozyrev, A. N.; Kozyrev, E. A.; Krokovny, P. P.; Kuzmenko, A. E.; Kuzmin, A. S.; Logashenko, I. B.; Lukin, P. A.; Lysenko, A. P.; Mikhailov, K. Yu.; Obraztsov, I. V.; Okhapkin, V. S.; Otboev, A. V.; Perevedentsev, E. A.; Pestov, Yu. N.; Popov, A. S.; Razuvaev, G. P.; Rogovsky, Yu. A.; Ruban, A. A.; Ryskulov, N. M.; Ryzhenenkov, A. E.; Semenov, A. V.; Senchenko, A. I.; Shatunov, P. Yu.; Shatunov, Yu. M.; Shebalin, V. E.; Shemyakin, D. N.; Shwartz, B. A.; Shwartz, D. B.; Sibidanov, A. L.; Solodov, E. P.; Talyshev, A. A.; Timoshenko, M. V.; Titov, V. M.; Tolmachev, S. S.; Vorobiov, A. I.; Zemlyansky, I. M.; Zhadan, D. S.; Zharinov, Yu. M.; Zubakin, A. S.; Yudin, Yu. V.
Source
Phys. Rev. D 109, 112002 (2024)
Subject
Language
Abstract
The cross section of the process $e^+e^-\to\pi^+\pi^-$ has been measured in the center of mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on a full dataset collected below 1 GeV during three data taking seasons, corresponding to an integrated luminosity of about 62 pb$^{-1}$. In the dominant $\rho$-resonance region, a systematic uncertainty of 0.7% has been reached. At energies around $\phi$-resonance the $\pi^+\pi^-$ production cross section was measured for the first time with high beam energy resolution. The forward-backward charge asymmetry in the $\pi^+\pi^-$ production has also been measured. It shows a strong deviation from the theoretical prediction based on the conventional scalar quantum electrodynamics framework, and it is in good agreement with the generalized vector-meson-dominance and dispersive-based predictions. The impact of the presented results on the evaluation of the hadronic contribution to the anomalous magnetic moment of muon is discussed.
Comment: 54 pages, 36 figures; as published in Phys. Rev. D 109, 112002
Comment: 54 pages, 36 figures; as published in Phys. Rev. D 109, 112002