A5034086874- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Computational Physics and Python Applications
- Particle Detector Development and Performance
- Black Holes and Theoretical Physics
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Superconducting Materials and Applications
- Atomic and Subatomic Physics Research
- Nuclear physics research studies
- Stochastic processes and statistical mechanics
- Radiation Detection and Scintillator Technologies
- International Science and Diplomacy
- Distributed and Parallel Computing Systems
- Cosmology and Gravitation Theories
- Advanced NMR Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Markov Chains and Monte Carlo Methods
- Radioactive Decay and Measurement Techniques
- Advanced Data Storage Technologies
- Particle accelerators and beam dynamics
Université Paris-Saclay
2017-2025
Institut National de Physique Nucléaire et de Physique des Particules
2016-2025
Centre National de la Recherche Scientifique
2016-2025
European Organization for Nuclear Research
2023-2025
Laboratoire de Physique des 2 Infinis Irène Joliot-Curie
2020-2025
Université Paris-Sud
2008-2020
École Polytechnique Fédérale de Lausanne
2010-2020
GANIL
2017-2020
Budker Institute of Nuclear Physics
2015
Siberian Branch of the Russian Academy of Sciences
2015
The LHCb experiment is dedicated to precision measurements of CP violation and rare decays B hadrons at the Large Hadron Collider (LHC) CERN (Geneva). initial configuration expected performance detector associated systems, as established by test beam simulation studies, described.
This article reports world averages of measurements $b$-hadron, $c$-hadron, and $\tau$-lepton properties obtained by the Heavy Flavor Averaging Group using results available through summer 2016. For averaging, common input parameters used in various analyses are adjusted (rescaled) to values, known correlations taken into account. The include branching fractions, lifetimes, neutral meson mixing parameters, \CP~violation semileptonic decays CKM matrix elements.
Observations of exotic structures in the J/ψp channel, which we refer to as charmonium-pentaquark states, Λ0b→J/ψK−p decays are presented. The data sample corresponds an integrated luminosity 3 fb−1 acquired with LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis three-body final state reproduces two-body mass angular distributions. To obtain a satisfactory fit seen spectrum, it is necessary include two Breit-Wigner amplitudes that each describe resonant state. significance...
A measurement of the ratio branching fractions $B^{+}\rightarrow K^{+}\mu^{+}\mu^{-}$ and K^{+}e^{+}e^{-}$ decays is presented using proton-proton collision data, corresponding to an integrated luminosity 3.0 fb$^{-1}$, recorded with LHCb experiment at center-of-mass energies 7 8 $\mathrm{\,Te\kern -0.1em V}$. The value for dilepton invariant mass squared range $1<q^{2}<6\mathrm{\,Ge\kern V^2\!/}c^4$ measured be $0.745^{+0.090}_{-0.074}\mathrm{\,(stat)}\,\pm0.036\mathrm{\,(syst)}$. This most...
The branching fraction ratio R(D^{*})≡B(B[over ¯]^{0}→D^{*+}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]^{0}→D^{*+}μ^{-}ν[over ¯]_{μ}) is measured using a sample of proton-proton collision data corresponding to 3.0 fb^{-1} integrated luminosity recorded by the LHCb experiment during 2011 and 2012. tau lepton identified in decay mode τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ}. semitauonic sensitive contributions from non-standard-model particles that preferentially couple third generation fermions, particular,...
A narrow pentaquark state, P_{c}(4312)^{+}, decaying to J/ψp, is discovered with a statistical significance of 7.3σ in data sample Λ_{b}^{0}→J/ψpK^{-} decays, which an order magnitude larger than that previously analyzed by the LHCb Collaboration. The P_{c}(4450)^{+} structure formerly reported confirmed and observed consist two overlapping peaks, P_{c}(4440)^{+} P_{c}(4457)^{+}, where this two-peak interpretation 5.4σ. proximity Σ_{c}^{+}D[over ¯]^{0} ¯]^{*0} thresholds peaks suggests they...
We present a measurement of form-factor-independent angular observables in the decay ${B}^{0}\ensuremath{\rightarrow}{K}^{*}(892{)}^{0}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$. The analysis is based on data sample corresponding to an integrated luminosity $1.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$, collected by LHCb experiment $pp$ collisions at center-of-mass energy 7 TeV. Four are measured six bins dimuon invariant mass squared ${q}^{2}$ range...
An angular analysis of the B 0 → K *0(→ + π −)μ μ − decay is presented. The dataset corresponds to an integrated luminosity 3.0 fb−1 pp collision data collected at LHCb experiment. complete information from used determine CP-averaged observables and CP asymmetries, taking account possible contamination decays with system in S-wave configuration. their correlations are reported bins q 2, invariant mass squared dimuon system. determined both unbinned maximum likelihood fit by using principal...
A measurement of the ratio branching fractions decays B^{+}→K^{+}μ^{+}μ^{-} and B^{+}→K^{+}e^{+}e^{-} is presented. The proton-proton collision data used correspond to an integrated luminosity 5.0 fb^{-1} recorded with LHCb experiment at center-of-mass energies 7, 8, 13 TeV. For dilepton mass-squared range 1.1<q^{2}<6.0 GeV^{2}/c^{4} measured be R_{K}=0.846_{-0.054}^{+0.060}_{-0.014}^{+0.016}, where first uncertainty statistical second systematic. This most precise R_{K} date compatible...
Resonant structures in B^{0}→ψ^{'}π^{-}K^{+} decays are analyzed by performing a four-dimensional fit of the decay amplitude, using pp collision data corresponding to 3 fb^{-1} collected with LHCb detector. The cannot be described K^{+}π^{-} resonances alone, which is confirmed model-independent approach. A highly significant Z(4430)^{-}→ψ^{'}π^{-} component required, thus confirming existence this state. observed evolution Z(4430)^{-} amplitude ψ^{'}π^{-} mass establishes resonant nature...
A search for the rare decays ${B}_{s}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ and ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ is performed with data collected in 2011 2012 LHCb experiment at Large Hadron Collider. The samples comprise $1.1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of proton-proton collisions $\sqrt{s}=8\text{ }\mathrm{TeV}$ $1.0\text{ $\sqrt{s}=7\text{ }\mathrm{TeV}$. We...
The quantum numbers of the X(3872) meson are determined to be JPC = 1++ based on angular correlations in B+ K+ decays, where pi+pi- J/psi and \mu+\mu-. data correspond 1.0 fb-1 pp collisions collected by LHCb detector. only alternative assignment allowed previous measurements, JPC=2-+, is rejected with a confidence level equivalent more than eight Gaussian standard deviations using likelihood-ratio test full phase space. This result favors exotic explanations state.
This paper reports world averages of measurements $b$-hadron, $c$-hadron, and $\tau$-lepton properties obtained by the Heavy Flavor Averaging Group using results available through September 2018. In rare cases, significant several months later are also used. For averaging, common input parameters used in various analyses adjusted (rescaled) to values, known correlations taken into account. The include branching fractions, lifetimes, neutral meson mixing parameters, CP violation semileptonic...
The production of J/psi mesons in proton-proton collisions at sqrt(s)=7 TeV is studied with the LHCb detector LHC. differential cross-section for prompt measured as a function transverse momentum pT and rapidity y fiducial region 0<pT<14 GeV/c 2.0<y<4.5. fraction from b-hadron decays are also same ranges. analysis based on data sample corresponding to an integrated luminosity 5.2pb-1. cross-sections over 10.52 +/- 0.04 1.40 +1.64/-2.20 mub 1.14 0.01 0.16 decays, where first uncertainty...
A search for the rare decays ${B}_{s}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ and ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ is performed at LHCb experiment. The data analyzed correspond to an integrated luminosity of $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ $pp$ collisions a center-of-mass energy 7 TeV $2\text{ 8 TeV. An excess signal candidates with respect background expectation seen...
The $\Xi_c^+ K^-$ mass spectrum is studied with a sample of $pp$ collision data corresponding to an integrated luminosity 3.3 fb$^{-1}$, collected by the LHCb experiment. $\Xi_c^+$ reconstructed in decay mode $p K^- \pi^+$. Five new, narrow excited $\Omega_c^0$ states are observed: $\Omega_c(3000)^0$, $\Omega_c(3050)^0$, $\Omega_c(3066)^0$, $\Omega_c(3090)^0$, and $\Omega_c(3119)^0$. Measurements their masses widths reported.
Abstract Conventional, hadronic matter consists of baryons and mesons made three quarks a quark–antiquark pair, respectively 1,2 . Here, we report the observation state containing four in Large Hadron Collider beauty experiment. This so-called tetraquark contains two charm quarks, $$\overline{{{{{u}}}}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mover> <mml:mrow> <mml:mi>u</mml:mi> </mml:mrow> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> $$\overline{{{{{d}}}}}$$...
During 2011 the LHCb experiment at CERN collected 1.0 fb−1 of $\sqrt{s} = 7\mbox{~TeV}$ pp collisions. Due to large heavy quark production cross-sections, these data provide unprecedented samples flavoured hadrons. The first results from have made a significant impact on flavour physics landscape and definitively proved concept dedicated in forward region hadron collider. This document discusses implications measurements classes extensions Standard Model, bearing mind interplay with searches...
This paper reports world averages of measurements $b$-hadron, $c$-hadron, and $\tau$-lepton properties obtained by the Heavy Flavour Averaging Group using results available before April 2021. In rare cases, significant several months later are also used. For averaging, common input parameters used in various analyses adjusted (rescaled) to values, known correlations taken into account. The include branching fractions, lifetimes, neutral meson mixing parameters, CP violation semileptonic...
A bstract search for $$ {B}_s^0\to {\overline{D}}^0{f}_0(980) <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msubsup><mml:mi>B</mml:mi><mml:mi>s</mml:mi><mml:mn>0</mml:mn></mml:msubsup><mml:mo>→</mml:mo><mml:msup><mml:mover><mml:mi>D</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mn>0</mml:mn></mml:msup><mml:msub><mml:mi>f</mml:mi><mml:mn>0</mml:mn></mml:msub><mml:mfenced><mml:mn>980</mml:mn></mml:mfenced></mml:math> decays is performed using 3 . 0 fb 1− of pp collision data...
Charm production at the LHC in pp collisions s=7TeV is studied with LHCb detector. The decays D0→K−π+, D+→K−π+π+, D⁎+→D0(K−π+)π+, Ds+→ϕ(K−K+)π+, Λc+→pK−π+, and their charge conjugates are analysed a data set corresponding to an integrated luminosity of 15 nb−1. Differential cross-sections dσ/dpT measured for prompt five charmed hadron species bins transverse momentum rapidity region 0<pT<8GeV/c 2.0<y<4.5. Theoretical predictions compared differential cross-sections. charm hadrons computed...
An angular analysis and a measurement of the differential branching fraction decay B 0 → ϕμ + μ − are presented, using data corresponding to an integrated luminosity 3.0 fb−1 pp collisions recorded by LHCb experiment at $$ \sqrt{s}=7 8 TeV. Measurements reported as function q 2, square dimuon invariant mass results found be consistent with Standard Model. In range 1 < 2 6 GeV2 /c 4, where precise theoretical calculations available, is more than 3σ below Model predictions.
The isospin asymmetries of $B \to K\mu^+\mu^-$ and K^{*}\mu^+\mu^-$ decays the partial branching fractions $B^0 K^0\mu^+\mu^-$, $B^+ K^+\mu^+\mu^-$ K^{*+}\mu^+\mu^-$ are measured as functions dimuon mass squared, $q^2$. data used correspond to an integrated luminosity 3$~$fb$^{-1}$ from proton-proton collisions collected with LHCb detector at centre-of-mass energies 7$\,$TeV 8$\,$TeV in 2011 2012, respectively. both consistent Standard Model expectations. three fractions, while individually...
Quantum chromodynamics, the theory of strong force, describes interactions coloured quarks and gluons formation hadronic matter. Conventional matter consists baryons mesons made three quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported narrow state in D
The first full amplitude analysis of $B^+\to J/ψϕK^+$ with $J/ψ\toμ^+μ^-$, $ϕ\to K^+K^-$ decays is performed a data sample 3 fb$^{-1}$ $pp$ collision collected at $\sqrt{s}=7$ and $8$ TeV the LHCb detector. cannot be described by model that contains only excited kaon states decaying into $ϕK^+$, four $J/ψϕ$ structures are observed, each significance over $5$ standard deviations. quantum numbers these determined least $4$ lightest has mass consistent with, but width much larger than, previous...