Related papers: Probing QCD Axions or Axion-like Particles in thre…

We study rare three- and four-body kaon decays as a probe of light vector and axial-vector bosons coupled to non-conserved currents. We find that searches for $K_L \to \pi^0 \pi^0 (X\to e^+e^-)$ decays constrain the couplings of light $X$…

We analyze the three-body decays of the long-lived neutral kaon $K_L \to \pi\pi a$, where $a$ is an axion-like particle (ALP), and compare them to the two-body decay $K_L \to \pi^0 a$. While the latter requires both flavor violation (FV)…

We point out kaon decays to multiple charged leptons as a novel probe of light dark particles $X$. Previously neglected channels, such as $K^+\to \pi^+ \left(XX \to 2(e^+e^-)\right)$, $K_L\to \pi^0 \left( XX \to 2(e^+e^-)\right)$, and…

Rare kaon decays provide sensitive tests of new physics. In this work, we focus on scalar and pseudoscalar operators, analysing the $K\to \pi \ell^+\ell^-$ and $K\to \ell^+\ell^-$ decays. We highlight the complementary role of different…

In this work, we studied the quasi-two-body decays $B_{(s)} \to \psi [K^*(892), K^*(1410),$ $K^*(1680)] \to \psi K\pi$ by employing the perturbative QCD (PQCD) factorization approach, where the charmonia $\psi$ represents $J/\psi$ and…

A high statistics data sample of the $K^{+}$ decays is recorded by the OKA collaboration. A missing mass analysis is performed to search for a light invisible pseudoscalar axion-like particle (ALP) $a$ in the decay $K^{+} \to \pi^{+}…

The newly-discovered $\Xi_{cc}^{++}$ decays into the $ \Lambda_{c}^+ K^-\pi^+\pi^+$, but the experimental data has indicated that this decay is not saturated by any two-body intermediate state. In this work, we analyze the multi-body weak…

LHCb Collaboration studied the resonant structure of $B_s\to \overline{D}^0K^-\pi^+$ decays using the Dalitz plot analysis technique, based on a data sample corresponding to an integrated luminosity of $3.0{\rm fb}^{-1}$ of $pp$ collision.…

Three-body $B$ decays not only significantly broaden the study of $B$ meson decay mechanisms, but also provide information of resonant particles. Because of complicate dynamics, it is very hard for us to study the whole phase space in a…

An interesting proposal suggests that a QCD axion $(a)$ coupling to the up quark, down quark, and electron remains viable for an axion mass near 10~MeV. In this paper, this possibility is reexamined by deriving new bounds from kaon decays.…

We describe a novel search strategy for axions (or hadronically coupled axion-like particles) in the mass range of $m_a \lesssim 350\,{\rm MeV}$. The search relies on kaon decay at rest, which produces a mono-energetic signal in a large…

We study the quasi-two-body decays $B\to D K^*(892) \to D K\pi$ by employing the perturbative QCD approach. The two-meson distribution amplitudes $\Phi_{K\pi}^{\text{$P$-wave}}$ are adopted to describe the final state interactions of the…

The LHCb Collaboration announced the observation of doubly charmed baryon through $\Xi_{c c}^{++} \rightarrow \Lambda_{c}^{+} K^{-} \pi^{+} \pi^{+}$ in 2017. Since then, a series of studies of doubly heavy baryons have been presented.…

Different from the previous treatment in a two-body framework, we introduce the dimeson distribution amplitudes (DAs) to describe the strong dynamics between the S-wave resonances $a_0(980, 1450)$ and the $K\bar K (\pi\eta)$ pair, where the…

Nucleon decays into a lepton and two pseudoscalar mesons represent key channels for probing baryon number violation, complementing conventional two-body modes. In this Letter, we model-independently correlate two- and three-body processes…

The theoretical calculation for pseudo--scalars hadronic decays $K \to \pi a$ is reviewed. %with the Axion-Like-Particle escaping the detection, While one-loop penguin contributions are usually considered, tree-level processes have most…

The quasi-two-body $B \to D (R\to) K \pi$ decays are calculated in PQCD approach based on the $k_T$ factorization by introducing the wave functions of $K\pi$ pair associated with the resonances $K^*(892)$, $K_0^*(1430)$ and $K_2^*(1430)$.…

We study the sensitivity of fixed target experiments to hadronically-coupled axion like particles (ALPs) produced in kaon decays, with a particular emphasis on current and upcoming short-baseline neutrino experiments. We demonstrate that…

The hadronic decays $B\to J/\psi K(K^*)$ are interesting because experimentally they are the only color-suppressed modes which have been measured, and theoretically they are calculable by QCD factorization even the emitted meson $J\psi$ is…

Axion-like particles (ALPs), relatively light (pseudo-)scalars coupled to two gauge bosons, are a common feature of many extensions of the Standard Model. Up to now there has been a gap in the sensitivity to such particles in the MeV to 10…