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Effect of the $K^{*}$ meson magnetic dipole moment on the $e^{+} e^{-} \to K^{+} K^{-} π^{0} π^{0}$ cross section

Luis A. Jiménez Pérez , Antonio Rojas , and Genaro Toledo

Instituto de Física, Universidad Nacional Autónoma de México, AP 20-364, Ciudad de México 01000, México

Phys. Rev. D 114, 016031 – Published 31 July, 2026

DOI: https://doi.org/10.1103/bbrb-bg8r

Abstract

We explore the sensitivity of the $e^{+} e^{-} \to K^{+} K^{-} 2 π^{0}$ cross section to the magnetic dipole moment (MDM) of the $K^{*}$ vector meson. We describe the $γ^{*} \to 2 K 2 π$ vertex using a vector meson dominance model, including the intermediate resonant contributions relevant for energies below 2.4 GeV. Using $B A B A R$ data for this process, we show that this observable is indeed sensitive to the MDM of the $K^{*}$ ; we obtain a central value for the MDM of $μ_{K^{*}} = 4.5$ and an upper bound of ${\bar{μ}}_{K^{*}} = 6.3$ , in units of $e / 2 m_{K^{*}}$ . We emphasize the need for higher precision data to provide a first data-driven determination of this parameter to confront it with theoretical predictions.

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Phys. Rev. D 114, 016031– Published 31 July, 2026

Vol. 114, Iss. 1 — 1 July 2026

Received 22 April 2026
Accepted 22 June 2026

DOI: https://doi.org/10.1103/bbrb-bg8r

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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Effect of the $K^{*}$ meson magnetic dipole moment on the $e^{+} e^{-} \to K^{+} K^{-} π^{0} π^{0}$ cross section

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Effect of the K* meson magnetic dipole moment on the e+e−→K+K−π0π0 cross section

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References (62)

Effect of the $K^{*}$ meson magnetic dipole moment on the $e^{+} e^{-} \to K^{+} K^{-} π^{0} π^{0}$ cross section