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Time-like electromagnetic form factors of $Λ, Σ$ , and $Ξ^{+}$ in a light-front quark model

Chongqing University of Posts and Telecommunications, Chongqing 400065, China and School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China

^*Contact author: cclih123@gmail.com
^†Contact author: cqgeng@ucas.ac.cn

Phys. Rev. C 113, 055501 – Published 12 May, 2026

DOI: https://doi.org/10.1103/nsvk-4sjg

Abstract

We use the light front quark model to investigate the form factors in the $e^{+} e^{-} \to B \bar{B}$ collision proceses with $B = Λ, Σ$ and $Ξ$ . These form factor behaviors are calculated based on the Bethe-Salpeter formalism with $q^{+} > 0$ to effectively account for nonvalence contributions. We show that our results of the $q^{2}$ -dependent form factors closely match the BESIII data. In particular, we obtain that $| G_{eff} | = (0.921, 0.098, 0.189$ ) and $R = | \frac{G_{E}}{G_{M}} | = (0.97, 0.89, 0.936)$ for $e^{+} e^{-} \to Λ \bar{Λ}, Σ^{+} Σ^{-}, Ξ^{+} Ξ^{+})$ with $q^{2} = (5.74, 6.0, 7.0) {GeV}^{2}$ .

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Phys. Rev. C 113, 055501– Published 12 May, 2026

Vol. 113, Iss. 5 — May 2026

Received 8 January 2026
Revised 21 March 2026
Accepted 10 April 2026

DOI: https://doi.org/10.1103/nsvk-4sjg

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP³.

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Time-like electromagnetic form factors of $Λ, Σ$ , and $Ξ^{+}$ in a light-front quark model

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Time-like electromagnetic form factors of Λ, Σ, and Ξ+ in a light-front quark model

Abstract

Physics Subject Headings (PhySH)

Article Text

References (47)

Time-like electromagnetic form factors of $Λ, Σ$ , and $Ξ^{+}$ in a light-front quark model