{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:48:12Z","timestamp":1760150892740,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T00:00:00Z","timestamp":1643673600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The investigation of the fundamental properties of the nucleon is one of the most important topics in the modern hadron physics. Its internal structure and dynamics can be studied through the measurement of electromagnetic form factors which represent the simplest structure observables and serve as a test ground for our understanding of the strong interaction. Since the first attempt to measure the time-like form factors of the neutron, only four experiments published results on its structure from annihilation reactions. Due to the lack of statistics and experimental challenges, no individual determination of the form factors of the neutron has been possible so far. Modern developments of electron-positron colliders and the associated detectors allow to measure the effective FF of the neutron with the process e+e\u2212\u2192nn\u00af with unprecedented precision at the BESIII experiment, which is based at the BEPCII collider in Beijing, China. In this report, we review the published results of the form factors on the neutron in the time-like regime, describe the experimental setup, and discuss their impact on our understanding of the strong interaction. Future works at BESIII will help to improve the precision of the neutron FFs and, combined with theoretical progress in this field, help to illuminate the properties of the neutron structure.<\/jats:p>","DOI":"10.3390\/sym14020298","type":"journal-article","created":{"date-parts":[[2022,2,1]],"date-time":"2022-02-01T22:16:18Z","timestamp":1643753778000},"page":"298","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Electromagnetic Structure of the Neutron from Annihilation Reactions"],"prefix":"10.3390","volume":"14","author":[{"given":"Paul","family":"Larin","sequence":"first","affiliation":[{"name":"Helmholtz Institute Mainz, Staudinger Weg 18, D-55099 Mainz, Germany"},{"name":"Institute of Nuclear Physics, Johannes Gutenberg University, D-55128 Mainz, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7671-7644","authenticated-orcid":false,"given":"Xiaorong","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Particle Detection and Electronics, Hefei 230026, China"},{"name":"Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8227-4544","authenticated-orcid":false,"given":"Jifeng","family":"Hu","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Nuclear Science, Institute of Quantum Matter, South China Normal University, Guangzhou 510631, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9271-1883","authenticated-orcid":false,"given":"Frank","family":"Maas","sequence":"additional","affiliation":[{"name":"Helmholtz Institute Mainz, Staudinger Weg 18, D-55099 Mainz, Germany"},{"name":"Institute of Nuclear Physics, Johannes Gutenberg University, D-55128 Mainz, Germany"},{"name":"GSI Helmholtzzentrum f\u00fcr Schwerionenforschung GmbH, D-64291 Darmstadt, Germany"}]},{"given":"Rinaldo Ferroli","family":"Baldini","sequence":"additional","affiliation":[{"name":"INFN Laboratori Nazionali di Frascati, I-00044 Frascati, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9958-379X","authenticated-orcid":false,"given":"Haiming","family":"Hu","sequence":"additional","affiliation":[{"name":"Institute of High Energy Physics, Beijing 100049, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7510-3181","authenticated-orcid":false,"given":"Guangshun","family":"Huang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Particle Detection and Electronics, Hefei 230026, China"},{"name":"Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1103\/PhysRev.110.552","article-title":"Magnetic Form Factor of the Neutron","volume":"110","author":"Yearian","year":"1958","journal-title":"Phys. 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