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arXiv · 2508.16222

Analysis of $B\to KM_X$ and $B\to K^* M_X$ decays in scalar- and vector-mediator dark-matter scenarios

Alexander Berezhnoy·Wolfgang Lucha·Dmitri Melikhov
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Abstract

The surprising excess of missing-energy events far beyond all standard-model expectations in the weak decays of the charged ground-state $B^+$ meson into some charged strange meson, rather recently observed by the Belle-II experiment, may (easily) be explained by the decay of the $B$ meson into the strange meson and a pair of dark-matter fermion and antifermion, mediated by an (intermediate) scalar or vector boson. Thorough inspections of both the total and the differential widths of these decays provide, among others, a simple means for the (straightforward) discrimination of such mediator boson's scalar or vector nature.

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Alexander Berezhnoy, Wolfgang Lucha, Dmitri Melikhov. 2025-08-22. Analysis of $B\to KM_X$ and $B\to K^* M_X$ decays in scalar- and vector-mediator dark-matter scenarios. https://doi.org/10.3103/s0027134925702339

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