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Dark matter emission at Belle II and NA62 in the minimal flavor violation framework

Federico Mescia ¹, Shohei Okawa ^2,3,4, Joel Swallow ⁵, and Claudio Toni ⁶

¹Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati, C.P. 13, 00044 Frascati, Italy
²Asia Pacific Center for Theoretical Physics, Pohang, 37673, Korea
³Department of Physics, Pohang University of Science and Technology, Pohang, 37673, Korea
⁴Department of Physics, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
⁵CERN, European Organization for Nuclear Research, CH-1211 Geneva 23, Switzerland
⁶LAPTh, Université Savoie Mont-Blanc et CNRS, 74941 Annecy, France

Phys. Rev. D 113, 095014 – Published 7 May, 2026

DOI: https://doi.org/10.1103/7dlz-bwlz

Abstract

Minimal flavor violation (MFV) provides a compelling framework for exploring physics beyond the Standard Model, in which new QCD-singlet fields transforming under the global $SU (3)^{3}$ quark flavor symmetry can naturally be stable and act as dark matter (DM) candidates. We show that the DM–MFV framework naturally accommodates the excess in either $K^{+} \to π^{+} ν \bar{ν}$ or $B^{+} \to K^{+} ν \bar{ν}$ , while a unified explanation of both channels simultaneously cannot be achieved within a minimal setup containing only a single dark matter multiplet with nearly degenerate masses. Overall, our findings underscore the intricate interplay between MFV-based model building, flavored dark matter scenarios, and precision flavor experiments, highlighting flavored dark matter as a framework that is both theoretically robust and experimentally testable.

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References (94)

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Phys. Rev. D 113, 095014– Published 7 May, 2026

Vol. 113, Iss. 9 — 1 May 2026

Received 22 January 2026
Accepted 21 April 2026

DOI: https://doi.org/10.1103/7dlz-bwlz

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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Dark matter emission at Belle II and NA62 in the minimal flavor violation framework

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