Measurement of the neutron timelike electric and magnetic form factors ratio at the VEPP-2000 $e^+e^-$ collider

M. N. Achasov; A. E. Alizzi; A. Yu. Barnyakov; E. V. Bedarev; K. I. Beloborodov; A. V. Berdyugin; A. G. Bogdanchikov; A. A. Botov; T. V. Dimova; V. P. Druzhinin; R. A. Efremov; V. N. Zhabin; V. V. Zhulanov; P. V. Zhulanova; L. V. Kardapoltsev; A. S. Kasaev; A. A. Kattsin; D. P. Kovrizhin; I. A. Koop; A. A. Korol; A. S. Kupich; A. P. Kryukov; N. A. Melnikova; N. Yu. Muchnoi; A. E. Obrazovsky; A. A. Oorzhak; I. V. Ovtin; E. V. Pakhtusova; I. A. Polomoshnov; K. V. Pugachev; S. A. Rastigeev; Yu. A. Rogovsky; A. I. Senchenko; S. I. Serednyakov; Z. K. Silagadze; K. D. Sungurov; I. K. Surin; Yu. V. Usov; A. G. Kharlamov; D. E. Chistyakov; D. A. Shtol

doi:10.1103/ynkd-4jzy

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arXiv · 2601.19185

Measurement of the neutron timelike electric and magnetic form factors ratio at the VEPP-2000 $e^+e^-$ collider

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Abstract

In the experiment to study the e+e->n+anti n process at the VEPP-2000 $e^+e^-$ collider, the ratio |GE|/|GM| of the neutron timelike electric and magnetic form factors has been measured. The experiment was carried out with the SND detector in the center-of-mass energy range 1890-2000 MeV in eight energy points with an integrated luminosity of 83 inv.pb. The |GE|/|GM| ratio is determined by the analyzing the distribution of the polar angle of the produced antineutron. The measured |GE|/|GM| value in the energy range under study is between 1.0 and 1.5 with an average value of 1.21+-0.13.

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M. N. Achasov, A. E. Alizzi, A. Yu. Barnyakov, E. V. Bedarev, K. I. Beloborodov, A. V. Berdyugin, A. G. Bogdanchikov, A. A. Botov, T. V. Dimova, V. P. Druzhinin, R. A. Efremov, V. N. Zhabin, V. V. Zhulanov, P. V. Zhulanova, L. V. Kardapoltsev, A. S. Kasaev, A. A. Kattsin, D. P. Kovrizhin, I. A. Koop, A. A. Korol, A. S. Kupich, A. P. Kryukov, N. A. Melnikova, N. Yu. Muchnoi, A. E. Obrazovsky, A. A. Oorzhak, I. V. Ovtin, E. V. Pakhtusova, I. A. Polomoshnov, K. V. Pugachev, S. A. Rastigeev, Yu. A. Rogovsky, A. I. Senchenko, S. I. Serednyakov, Z. K. Silagadze, K. D. Sungurov, I. K. Surin, Yu. V. Usov, A. G. Kharlamov, D. E. Chistyakov, D. A. Shtol. 2026-01-27. Measurement of the neutron timelike electric and magnetic form factors ratio at the VEPP-2000 $e^+e^-$ collider. https://doi.org/10.1103/ynkd-4jzy

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