相关论文: Dark light shining on $B\to K^{(*)} E_{\rm miss}$

We introduce a model-independent framework to reinterpret Belle II results using only public data, analytically reconstructing the mapping between true and reconstructed kinematic variables within the statistically dominant Inclusive…

We construct the minimal dark matter models in the left-right symmetric extensions of the standard model (SM), where the gauge symmetry SU(3)$_C\times$SU(2)$_L\times$SU(2)$_R\times$U(1)$_{B-L}$ is broken into its subgroup…

Belle II has recently reported the new measurement ${\cal B}(B^+\to K^+\nu\bar\nu)=(2.3\pm0.7)\times 10^{-5}$ \cite{Belle-II:2023esi} which is two times larger than their previous result (although consistent within errors) and about…

$L_\mu -L_\tau$ gauge boson ($Z'$) with a mass in the MeV to GeV region can resolve not only the muon $g-2$ excess, but also the gap in the high-energy cosmic neutrino spectrum at IceCube. It was recently proposed that such a light gauge…

Rare decays mediated by $b \to s \nu \bar \nu$ transitions have been reported by the Belle II experiment. The branching ratio of the decay $B^+ \to K^+ \nu \bar \nu$ is found to be enhanced with respect to the standard model value. If taken…

We propose an extension of the standard model with an extra U(1)' abelian symmetry, three Higgs doublets and one Higgs singlet, where the new U(1)' charges are flavour non-universal. As a result, the model introduces an enlarger particle…

We study scalar and fermionic crossing two-component dark matter (C2CDM) models with $ U(1)_X $ dark gauge symmetry. This $ U(1)_X $ gauge symmetry is broken via the dark Higgs mechanism of a dark Higgs field $\Phi$ and the dark photon…

We study an effective theory beyond the standard model (SM) where either of two additional gauge singlets, a Majorana fermion and a real scalar, constitutes all or some fraction of dark matter. In particular, we focus on the masses of the…

Dedicated underground experiments searching for dark matter have little sensitivity to GeV and sub-GeV masses of dark matter particles. We show that the decay of B mesons to K(K^*) and missing energy in the final state can be an efficient…

Theories beyond the standard model often predict the existence of an additional neutral boson, the $Z^{\prime}$. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the…

We report on recent results obtained by the Belle II experiment related to searches for beyond-the-standard-model physics. The $B$ meson decay data sample used corresponds to an integrated luminosity of $L = 189$ fb$^{-1}$. In recent years,…

We investigate the phenomenology of light GeV-scale fermionic dark matter in $U(1)_{L_\mu - L_{\tau}}$ gauge extension of the Standard Model. Heavy neutral fermions alongside with a $S_1(\overline{3}$,$1$,$1/3$) scalar leptoquark and an…

The direct searches for heavy scalar dark matter with a mass of order 100 GeV are much more sensitive than for light dark matter of order 1 GeV. The question arises whether dark matter could be light and has escaped detection so far. We…

We study UV complete theories where the Standard Model (SM) gauge group is extended with a new abelian $U(1)$, and the field content is augmented by an arbitrary number of scalar and fermion SM singlets, potentially including dark matter…

We propose a model realizes that a semi-visible dark photon which can contribute to the anomalous magnetic moment ($g-2$) of both electron and muon. In this model, the electron $g-2$ is deviated from the Standard Model (SM) prediction by…

The Belle II experiment at the SuperKEKB collider is a major upgrade of the KEK "$B$ factory" facility in Tsukuba, Japan. The machine is designed for an instantaneous luminosity of $8\times 10^{35}$~cm$^{-2}$\,s$^{-1}$, and the experiment…

The muon g-2 discrepancy between theory and experiment may be explained by a light vector boson Z_d that couples to the electromagnetic current via kinetic mixing with the photon. We illustrate how the existing electron g-2, pion Dalitz…

Dark photons with kinetic mixing are compelling mediators for the interactions between dark matter and Standard Model particles. While most experimental searches focus on fully visible or fully invisible decays of dark photons, we explore…

The possible existence of a new gauge boson U, light and very weakly coupled, allows for Light Dark Matter particles, which could also be at the origin of the 511 keV line from the galactic bulge. Independently of dark matter, and taking…

A search for dark matter is performed using events with large missing transverse momentum and a Higgs boson decaying either to a pair of bottom quarks or to a pair of photons. The data from proton-proton collisions at a center-of-mass…