Measurement of the neutron timelike electromagnetic form factor with the SND detector

SND Collaboration; M. N. Achasov; A. Yu. Barnyakov; E. V. Bedarev; K. I. Beloborodov; A. V. Berdyugin; D. E. Berkaev; A. G. Bogdanchikov; A. A. Botov; T. V. Dimova; V. P. Druzhinin; V. N. Zhabin; Yu. M. Zharinov; E. V. Kardapoltsev; A. S. Kasaev; D. P. Kovrizhin; I. A. Koop; A. A. Korol; A. S. Kupich; A. P. Kryukov; A. P. Lysenko; N. A. Melnikova; N. Yu. Muchnoy; A. E. Obrazovsky; E. V. Pakhtusova; K. V. Pugachev; S. A. Rastigeev; Yu. A. Rogovsky; S. I. Serednyakov; Z. K. Silagadze; I. K. Surin; Yu. V. Usov; A. G. Kharlamov; Yu. M. Shatunov; D. A. Shtol

arXiv · 2309.05241

Measurement of the neutron timelike electromagnetic form factor with the SND detector

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Abstract

The results of the measurement of the $e^+e^- \to n \bar{n}$ cross section and effective neutron timelike form factor are presented. The data taking was carried out in 2020-2021 at the VEPP-2000 $e^+e^-$ collider in the center-of-mass energy range from 1891 to 2007 MeV. The general purpose nonmagnetic detector SND is used to detect neutron-antineutron events. The event selection is performed using the time-of-flight technique. The measured cross section is 0.4-0.6 nb. The neutron form factor in the energy range under study varies from 0.3 to 0.2.

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SND Collaboration, M. N. Achasov, A. Yu. Barnyakov, E. V. Bedarev, K. I. Beloborodov, A. V. Berdyugin, D. E. Berkaev, A. G. Bogdanchikov, A. A. Botov, T. V. Dimova, V. P. Druzhinin, V. N. Zhabin, Yu. M. Zharinov, E. V. Kardapoltsev, A. S. Kasaev, D. P. Kovrizhin, I. A. Koop, A. A. Korol, A. S. Kupich, A. P. Kryukov, A. P. Lysenko, N. A. Melnikova, N. Yu. Muchnoy, A. E. Obrazovsky, E. V. Pakhtusova, K. V. Pugachev, S. A. Rastigeev, Yu. A. Rogovsky, S. I. Serednyakov, Z. K. Silagadze, I. K. Surin, Yu. V. Usov, A. G. Kharlamov, Yu. M. Shatunov, D. A. Shtol. 2023-09-11. Measurement of the neutron timelike electromagnetic form factor with the SND detector. https://arxiv.org/abs/2309.05241

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