C. Barschel
A5054491011- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Particle Accelerators and Free-Electron Lasers
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Medical Imaging Techniques and Applications
- Computational Physics and Python Applications
- Stochastic processes and statistical mechanics
- Radiation Detection and Scintillator Technologies
- Distributed and Parallel Computing Systems
- Cold Atom Physics and Bose-Einstein Condensates
- Nuclear physics research studies
- Advanced NMR Techniques and Applications
- International Science and Diplomacy
- Cosmology and Gravitation Theories
- Cryptography and Data Security
- Particle accelerators and beam dynamics
- advanced mathematical theories
- Physics of Superconductivity and Magnetism
- Advanced Authentication Protocols Security
European Organization for Nuclear Research
2011-2020
Imperial College London
2016-2017
Centro Brasileiro de Pesquisas Físicas
2013-2017
AGH University of Krakow
2015
École Polytechnique Fédérale de Lausanne
2014
Universidade de Santiago de Compostela
2011-2014
Institute for Nuclear Research
2014
University of Bristol
2013
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2011-2012
Forschungszentrum Jülich
2011
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,...
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 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.
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.
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...
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...
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...
Searches are performed for both prompt-like and long-lived dark photons, $A^{\prime}$, produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using $A^{\prime}\to\mu^+\mu^-$ decays data sample corresponding to an integrated luminosity 1.6 fb$^{-1}$ collected with the LHCb detector. The $A^{\prime}$ search covers mass range from near dimuon threshold up 70 GeV, while is restricted low-mass region $214<m(A^{\prime})<350$ MeV. No evidence signal found, 90% confidence level...
Measurements of $b$ hadron production ratios in proton-proton collisions at a centre-of-mass energy 7 TeV with an integrated luminosity 3 pb$^{-1}$ are presented. We study the strange $B$ meson to light $f_s/(f_u+f_d)$ and $\Lambda_b^0$ baryon $f_{\Lambda_b}/(f_u+f_d)$ as function charmed hadron-muon pair transverse momentum $p_T$ pseudorapidity $\eta$, for between 0 14 GeV $\eta$ 2 5. find that is consistent being independent $p_{\rm T}$ we determine = 0.134$\pm$ 0.004 $^{+0.011}_{-0.010}$,...
The production of $J/\psi$ pairs in proton-proton collisions at a centre-of-mass energy 7 TeV has been observed using an integrated luminosity $37.5 pb^{-1}$ collected with the LHCb detector. cross-section for both \jpsi rapidity range $2<y^{J/\psi}<4.5$ and transverse momentum $p_{T}^{J/\psi}<10 GeV/c$ is $$ \sigma^{J/\psi J/\psi} = 5.1\pm1.0\pm1.1 nb,$$ where first uncertainty statistical second systematic.
In the Standard Model of particle physics, strength couplings b quark to u and c quarks, |Vub| |Vcb|, are governed by coupling quarks Higgs boson. Using data from LHCb experiment at Large Hadron Collider, probability for Λb0 baryon decay into p final state relative is measured. Combined with theoretical calculations strong interaction a previously measured value first measurement use baryonic performed. This consistent previous determinations using B meson decays specific states confirms...
Evidence for the decay mode $X(3872)\rightarrow\psi(2S)\gamma$ in $B^+\rightarrow X(3872)K^+$ decays is found with a significance of 4.4 standard deviations. The analysis based on data sample proton-proton collisions, corresponding to an integrated luminosity 3fb$^{-1}$ collected LHCb detector, at centre-of-mass energies 7 and 8TeV. ratio branching fraction $X(3872)\to\psi(2S)\gamma$ that $X(3872)\rightarrow J/\psi \gamma$ measured be $$...
A full amplitude analysis of $\Lambda_b^0 \to J/\psi p \pi^-$ decays is performed with a data sample acquired the LHCb detector from 7 and 8 TeV $pp$ collisions, corresponding to an integrated luminosity 3 fb$^{-1}$. significantly better description achieved when, in addition previously observed nucleon excitations $N\to p\pi^-$, either $P_c(4380)^+$ $P_c(4450)^+\to p$ states, K^-$ decays, or $Z_c(4200)^-\to state, reported $B^0 K^+ all three, are included models. The support model...