Explore the vast range of titles available.

A model that can simultaneously explain Dark Matter relic density and the apparent matter anti-matter imbalance of the universe has been recently proposed. The model requires b-hadron branching fractions to Dark Matter at the per mille level. The b-hadrons decay to a dark sector baryon, ψDS, which has a mass in the region 940MeV/c2≤mψDS≤4430MeV/c2. In this paper, we discuss the sensitivity of the LHCb experiment to search for this dark baryon, covering different types of topology and giving prospects for Runs 3 and 4 of the LHC, as well as for the proposed Upgrade II. We show that the LHCb experiment can cover the entire mass range of the hypothetical dark baryon.

In this paper, we describe the potential of the LHCb experiment to detect Stealth physics. This refers to dynamics beyond the Standard Model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.

The resonant structure of the radiative decay Lambda(0)(b) -> pK(-) gamma in the region of proton-kaon invariant-mass up to 2.5 GeV/c(2) is studied using proton-proton collision data recorded at centre-of-mass energies of 7, 8, and 13TeV collected with the LHCb detector, corresponding to a total integrated luminosity of 9 fb(-1). Results are given in terms of fit and interference fractions between the different components contributing to this final state. Only. resonances decaying to pK(-) are found to be relevant, where the largest contributions stem from the Lambda(1520), Lambda(1600), Lambda(1800), and Lambda(1890) states.

The first observation of the Lambda(0)(b) -> D-s(-) p decay is presented using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of root s = 13TeV, corresponding to a total integrated luminosity of 6 fb(-1). Using the Lambda(0)(b) -> Lambda(+pi-)(c) decay as the normalisation mode, the branching fraction of the Lambda(0)(b) -> D-s(-) p decay is measured to be B (Lambda(0)(b) -> D-s(-) p) = (12.6 +/- 0.5 +/- 0.3 +/- 1.2) x 10(-6), where the first uncertainty is statistical, the second systematic and the third due to uncertainties in the branching fractions of the Lambda(0)(b) -> Lambda(+pi-)(c), D-s(-) -> K-K+pi(-) and Lambda(+)(c) -> pK(-)pi(+) decays.

Four decay modes of the B-c(+) meson into a J/psi meson and multiple charged kaons or pions are studied using proton-proton collision data, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13TeV and corresponding to an integrated luminosity of 9 fb(-1). The decay B-c(+) -> J/psi K+ K- pi(+)pi(+)pi(-) is observed for the first time, and evidence for the B-c(+) -> J/psi 4 pi(+)3 pi(-) decay is found. The decay B-c(+) -> J/psi 3 pi(+)2 pi(-) is observed and the previous observation of the B-c(+) -> psi(2S)pi(+)pi(+)pi(-) decay is confirmed using the psi(2S) -> J/psi pi(+)pi(-) decay mode. Ratios of the branching fractions of these four B-c(+) decay channels are measured.

A data set corresponding to an integrated luminosity of 9 fb(-1) of proton-proton collisions collected by the LHCb experiment has been analysed to search for D-(s)(()*())+ ((D) over bar)(*)0 decays. The decays are fully or partially reconstructed, where one or two (8) missing neutral pions or photons from the decay of an excited charm meson are allowed. Upper limits for the branching fractions, normalised to B+ decays to final states with similar topologies, are obtained for sixteen B-c(+) decay modes. For the decay B-c(+) -> D-s(+)(D) over bar (0), an excess with a significance of 3.4 standard deviations is found.

This article presents differential measurements of the asymmetry between \\varLambda_(b)⁰ and \\̅v̅a̅r̅L̅a̅m̅b̅d̅a̅_(b)⁰ baryon production rates in proton-proton collisions at centre-of-mass energies of √s̅ = 7 and 8 TeV collected with the LHCb experiment, corresponding to an integrated luminosity of 3 fb ⁻¹ . The \\varLambda_(b)⁰ baryons are reconstructed through the inclusive semileptonic decay \\varLambda_(b)⁰ → \\varLambda_(c)⁺ μ ⁻ ν̅ _(μ) X. The production asymmetry is measured both in intervals of rapidity in the range 2.15 < y < 4.10 and transverse momentum in 2 < p _(T) < 27 GeV/c. The results are found to be incompatible with symmetric production with a significance of 5.8 standard deviations for both √s̅ = 7 and 8 TeV data, assuming no CP violation in the decay. There is evidence for a trend as a function of rapidity with a significance of 4 standard deviations. Comparisons to predictions from hadronisation models in Pythia and heavy-quark recombination are provided. This result constitutes the first observation of a particle-antiparticle asymmetry in b-hadron production at LHC energies.[graphic not available: see fulltext]

Measurements of CP observables in B ± → DK ± and B ± → Dπ ± decays are presented, where D represents a superposition of D 0 and$$ {\\overline{D}}^0 $$D ¯ 0 states. The D meson is reconstructed in the three-body final states$$ {K}_{\\mathrm{S}}^0{K}^{\\pm }{\\pi}^{\\mp } $$K S 0 K ± π ∓ and$$ {K}_{\\mathrm{S}}^0{K}^{\\mp }{\\pi}^{\\pm } $$K S 0 K ∓ π ± . The analysis uses samples of B mesons produced in proton-proton collisions, corresponding to an integrated luminosity of 1.0, 2.0, and 6.0 fb − 1 collected with the LHCb detector at centre-of-mass energies of$$ \\sqrt{s} $$s = 7, 8, and 13 TeV, respectively. These measurements are the most precise to date, and provide important input for the determination of the CKM angle γ .

A model that can simultaneously explain Dark Matter relic density and the apparent matter anti-matter imbalance of the universe has been recently proposed. The model requires \\(b\\)-hadron branching fractions to Dark Matter at the per mille level. The \\(b\\)-hadrons decay to a dark sector baryon, \\(\\psi_{\\rm{DS}}\\), which has a mass in the region \\(940\\) MeV/c\\(^{2} \\leq m(\\psi_{\\rm{DS}}) \\leq 4430\\) MeV/c\\(^{2}\\). In this paper, we discuss the sensitivity of the LHCb experiment to search for this dark baryon, covering different types of topology and giving prospects for Runs 3 and 4 of the LHC, as well as for the proposed Phase-II Upgrade. We show that the LHCb experiment can cover the entire mass range of the hypothetical dark baryon.