Related papers: Dark photons from charm mesons at LHCb

A search for $K_{\textrm{S(L)}}^0\rightarrow\mu^{+}\mu^{-}\mu^{+}\mu^{-}$ decays is performed using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of 13 TeV, corresponding to an integrated…

The first model-independent measurement of the charm mixing parameters in the decay $D^0 \to K_S \pi^+ \pi^-$ is reported, using a sample of $pp$ collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of…

This paper presents the design of the LHCb trigger and its performance on data taken at the LHC in 2011. A principal goal of LHCb is to perform flavour physics measurements, and the trigger is designed to distinguish charm and beauty decays…

Motivated by dark-photon $\bar{\gamma}$ scenarios extensively considered in the literature, we explore experimentally allowed models where the Higgs boson coupling to photon and dark photon $H\gamma\bar{\gamma}$ can be enhanced.…

The Heavy Photon Search (HPS) experiment is designed to search for a new vector boson $A^\prime$ in the mass range of 20 MeV/$c^2$ to 220 MeV/$c^2$ that kinetically mixes with the Standard Model photon with couplings $\epsilon^2 >10^{-10}$.…

The Heavy Photon Search experiment took its first data in a 2015 engineering run at the Thomas Jefferson National Accelerator Facility, searching for a prompt, electro-produced dark photon with a mass between 19 and 81 MeV/$c^2$. A search…

A method for selecting and/or rejecting leptons from charm semileptonic decays based on the tagging of the secondary vertex using a hadron track is introduced. The method is developed for dimuon Drell-Yan measurements in LHCb using full…

We point out opportunities to probe invisible particles, left- and right-handed neutrinos, axion-like particles (ALPs) and dark photons $(Z^\prime)$ with rare decays of charm hadrons. We employ and recast existing searches in $D \to (\pi,…

Soft displaced leptons are representative collider signatures of compressed dark sectors with feeble couplings to the standard model. Prime targets are dark matter scenarios where co-scattering or co-annihilation sets the relic abundance…

The search for dark matter and other photon-portal long-lived particles (LLPs) at electron-positron colliders often relies on the mono-photon signature. At future Higgs factories operating at the $Z$-pole, this approach faces a critical…

A search is presented for a hidden-sector boson, $\chi$, produced in the decay $B^0 \rightarrow K^* (892)^0 \chi$, with $K^* (892)^0 \rightarrow K^+ \pi^-$ and $\chi \rightarrow \mu^+ \mu^-$ . The search is performed using a $pp$-collision…

LHCb has collected the world's largest sample of charmed hadrons. This sample is used to search for direct and indirect CP violation in charm and to measure $D^0$ mixing parameters. Preliminary measurements from several decay modes are…

Light new particles can be emitted in decays of excited nuclear states. Experiments analyzing such transitions and incorporating high-resolution detectors can be sensitive to new MeV-scale physics at a level competitive with upcoming…

Measurements performed with pairs of charm mesons produced at threshold from the decay of the $\psi(3770)$ resonance are of great value in flavour physics. The quantum correlation that exists between the two mesons allows unique access to…

A maverick top partner model, decaying to a dark photon was suggested. The dark photon decays to two overlapping electrons for dark photon masses of $\approx 100$ GeV, and results in a so-called lepton-jet. The event includes a top quark as…

Decays of $B^0$ and $B_{s}^0$ mesons to the charmless baryonic final states $p \overline{p} h^+ h^{\prime-}$, where $h$ and $h^\prime$ each denote a kaon or a pion, are searched for using the LHCb detector. The analysis is based on a sample…

A search for the nonresonant $\Lambda_c^+ \to p \mu^+ \mu^-$ decay is performed using proton-proton collision data recorded at a centre-of-mass energy of 13 TeV by the LHCb experiment, corresponding to an integrated luminosity of 5.4…

A study of $D^+\pi^-$, $D^0 \pi^+$ and $D^{*+}\pi^-$ final states is performed using pp collision data, corresponding to an integrated luminosity of 1.0 $fb^{-1}$, collected at a centre-of-mass energy of 7 TeV with the LHCb detector. The…

A search for the lepton-flavour violating decays $B^+ \to K^+ {\mu}^{\pm} e^{\mp}$ is performed using a sample of proton-proton collision data, collected with the LHCb experiment at centre-of-mass energies of $7$ and $8~{\rm TeV}$ and…

A sample of $4.687\times 10^6$ fully reconstructed $K^\pm\to\pi^\pm\pi^0_D$, $\pi^0_D\to\gamma e^+e^-$ decay candidates in the kinematic range $m_{ee}>10~{\rm MeV}/c^2$ with a negligible background contamination collected by the NA48/2…