# EP Articles

Letzte Einträge:
2020-01-06
15:42
 First observation of excited $\Omega_b^-$ states / LHCb Collaboration We report four narrow peaks in the $\Xi_b^0K^-$ mass spectrum obtained using $pp$ collisions at center-of-mass energies of 7, 8 and 13 TeV, corresponding to a total integrated luminosity of 9 fb$^{-1}$ recorded by the LHCb experiment. Referring to these states by their mass, the mass values are \begin{align*} m(\Omega_b(6316)^-) &= 6315.64\pm0.31\pm0.07\pm0.50 {\rm MeV}, \\ m(\Omega_b(6330)^-) &= 6330.30\pm0.28\pm0.07\pm0.50 {\rm MeV}, \\ m(\Omega_b(6340)^-) &= 6339.71\pm0.26\pm0.05\pm0.50 {\rm MeV}, \\ m(\Omega_b(6350)^-) &= 6349.88\pm0.35\pm0.05\pm0.50 {\rm MeV}, \end{align*}where the uncertainties are statistical, systematic and the last is due to the knowledge of the $\Xi_b^0$ mass. [...] arXiv:2001.00851; LHCb-PAPER-2019-042; CERN-EP-2019-278; LHCB-PAPER-2019-042.- Geneva : CERN, 2020-02-26 - 12 p. - Published in : Phys. Rev. Lett. 124 (2020) 082002 Article from SCOAP3: PDF; Fulltext: LHCb-PAPER-2019-042 - PDF; 2001.00851 - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

2019-12-05
10:43
 Isospin amplitudes in $\Lambda_b^0\to J/\psi \Lambda(\Sigma^0)$ and $\Xi_b^0\to J/\psi \Xi^0(\Lambda)$ decays / LHCb Collaboration Ratios of isospin amplitudes in hadron decays are a useful probe of the interplay between weak and strong interactions, and allow searches for physics beyond the Standard Model. We present the first results on isospin amplitudes in $b$-baryon decays, using data corresponding to an integrated luminosity of 8.5 fb$^{-1}$, collected with the LHCb detector in $pp$ collisions at center of mass energies of 7, 8 and 13 TeV. [...] arXiv:1912.02110; CERN-EP-2019-268; LHCb-PAPER-2019-039; LHCB-PAPER-2019-039-003; LHCB-PAPER-2019-039.- Geneva : CERN, 2020-03-17 - 11 p. - Published in : Phys. Rev. Lett. 124 (2020) 111802 Fulltext: 1912.02110 - PDF; DI-PRL-cascade - PDF; Fulltext from Publisher: PDF; Related data file(s): ZIP;

2019-11-21
13:46
 Precision measurement of the $\Xi_{cc}^{++}$ mass / LHCb Collaboration A measurement of the $\Xi_{cc}^{++}$ mass is performed using data collected by the LHCb experiment between 2016 and 2018 in $pp$ collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.6 $\mathrm{fb}^{-1}$. The $\Xi_{cc}^{++}$ candidates are reconstructed via the decay modes $\Xi_{cc}^{++}\to\Lambda_c^+K^-\pi^+\pi^+$ and $\Xi_{cc}^{++}\to\Xi_c^+\pi^+$. [...] arXiv:1911.08594; LHCb-PAPER-2019-037; CERN-EP-2019-258; LHCB-PAPER-2019-037.- 2020-02-07 - 18 p. - Published in : JHEP 2002 (2020) 049 Article from SCOAP3: PDF; Fulltext: LHCb-PAPER-2019-037_arXiv - PDF; 1911.08594 - PDF; Related data file(s): ZIP; Supplementary Information: ZIP;

2019-11-15
09:29
 Determination of quantum numbers for several excited charmed mesons observed in $B^- \to D^{*+} \pi^- \pi^-$ decays / LHCb Collaboration A four-body amplitude analysis of the $B^- \to D^{*+} \pi^- \pi^-$ decay is performed, where fractions and relative phases of the various resonances contributing to the decay are measured. Several quasi-model-independent analyses are performed aimed at searching for the presence of new states and establishing the quantum numbers of previously observed charmed meson resonances. [...] arXiv:1911.05957; CERN-EP-2019-201; LHCb-PAPER-2019-027; LHCB-PAPER-2019-027.- Geneva : CERN, 2020-02-21 - 24 p. - Published in : Phys. Rev. D 101 (2020) 032005 Article from SCOAP3: PDF; Fulltext: PDF; Related data file(s): ZIP;

2019-11-12
12:18
 Measurement of the $\eta_c(1S)$ production cross-section in $pp$ collisions at $\sqrt{s} = 13$ TeV / LHCb Collaboration Using a data sample corresponding to an integrated luminosity of $2.0\,fb^{-1}$, collected by the LHCb experiment, the production of the $\eta_c(1S)$ state in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=13 \text{ TeV}$ is studied in the rapidity range ${2.0 < y < 4.5}$ and in the transverse momentum range ${6.5 < p_{T} < 14.0\text{ GeV}}$. The cross-section for prompt production of $\eta_c(1S)$ mesons relative to that of the $J/\psi$ meson is measured using the ${p\bar{p}}$ decay mode and is found to be ${\sigma_{\eta_c(1S)}/\sigma_{J/\psi} = 1.69 \pm 0.15 \pm 0.10 \pm 0.18}$. [...] arXiv:1911.03326; LHCb-PAPER-2019-024; CERN-EP-2019-214; LHCB-PAPER-2019-024.- 2020-03-02 - 29 p. - Published in : Eur. Phys. J. C 80 (2020) 191 Article from SCOAP3: PDF; Fulltext: 1911.03326 - PDF; LHCb_PAPER_2019_024 - PDF; Related data file(s): ZIP; Supplementary information: ZIP;

2019-11-04
11:32
 Updated measurement of decay-time-dependent CP asymmetries in $D^0 \to K^+K^-$ and $D^0 \to \pi^+\pi^-$ decays / LHCb Collaboration A search for decay-time-dependent charge-parity ($CP$) asymmetry in $D^0 \to K^+K^-$ and $D^0 \to \pi^+\pi^-$ decays is performed at the LHCb experiment using proton-proton collision data recorded at a center-of-mass energy of 13TeV, and corresponding to an integrated luminosity of 5.4fb$^{-1}$. The $D^0$ mesons are required to originate from semileptonic decays of $b$ hadrons, such that the charge of the muon identifies the flavor of the neutral $D$ meson at production. [...] arXiv:1911.01114; CERN-EP-2019-225; LHCb-PAPER-2019-032; LHCB-PAPER-2019-032.- Geneva : CERN, 2020-01-14 - 12 p. - Published in : Phys. Rev. D 101 (2020) 012005 Article from SCOAP3: PDF; Figures: ZIP; Fulltext: LHCb-PAPER-2019-032 - PDF; 1911.01114 - PDF; Supplementary information: ZIP; External link: Figures

2019-10-22
16:33
 Measurement of $f_s / f_u$ variation with proton-proton collision energy and $B$-meson kinematics / LHCb Collaboration The ratio of the $B^0_s$ and $B^+$ fragmentation fractions $f_s$ and $f_u$ is studied with $B^0_s \to J/\psi \phi$ and $B^+ \to J/\psi K^+$ decays using data collected by the LHCb experiment in proton-proton collisions at 7, 8 and 13 TeV center-of-mass energies. The analysis is performed in bins of $B$-meson momentum, longitudinal momentum, transverse momentum, pseudorapidity and rapidity. [...] arXiv:1910.09934; CERN-EP-2019-209; LHCb-PAPER-2019-020; LHCB-PAPER-2019-020.- Geneva : CERN, 2020-03-26 - 11 p. - Published in : Phys. Rev. Lett. 124 (2020) 122002 Article from SCOAP3: scoap3-fulltext - PDF; 4a6db7d1849f361e0a2d3bda0b7927d6 - PDF; Fulltext: LHCb-PAPER-2019-020_arXiv - PDF; 1910.09934 - PDF; Related data files: ZIP;

2019-10-16
15:11
 Search for $A' \to \mu^+ \mu^-$ decays / LHCb Collaboration Searches are performed for both prompt-like and long-lived dark photons, $A'$, produced in proton-proton collisions at a center-of-mass energy of 13 TeV. These searches look for $A'\!\to\!\mu^+\mu^-$ decays using a data sample corresponding to an integrated luminosity of 5.5fb$^{-1}$ collected with the LHCb detector. [...] arXiv:1910.06926; LHCb-PAPER-2019-031; CERN-EP-2019-212; LHCB-PAPER-2019-031.- 2020-01-30 - 12 p. - Published in : Phys. Rev. Lett. 124 (2020) 041801 Article from SCOAP3: PDF; Fulltext: main - PDF; 1910.06926 - PDF; Related data file(s): ZIP;

2019-10-03
13:53
 More than preservation: Creating motivational designs and tailored incentives in research data repositories / Feger, Sebastian Stefan (CERN) Preserving and sharing are core reproducible practices that require substantial efforts in preparing and documenting research data analyses. Dedicated tools and services are developed to support researchers in this process. [...] CERN-OPEN-2019-007.- Geneva : CERN, 2019 - 5 p. Preprint: PDF; In : Open Repositories 2019, Hamburg, Hamburg, Germany, 10 - 14 Jun 2019, pp.Open Repositories 2019

2019-09-30
17:35
 Search for the doubly charmed baryon $\Xi_{cc}^{+}$ / LHCb Collaboration A search for the doubly charmed baryon $\Xi_{cc}^{+}$ is performed through its decay to the $\Lambda_c^+ K^- \pi^+$ final state, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13$\mathrm{\,Te\kern -0.1em V}$. The data correspond to a total integrated luminosity of $9\,\mathrm{fb}^{-1}$. [...] arXiv:1909.12273; LHCb-PAPER-2019-029; CERN-EP-2019-199; LHCB-PAPER-2019-029.- Geneva : CERN, 2019-11-19 - 15 p. - Published in : Sci. China Phys. Mech. Astron. 63 (2020) 221062 Fulltext: PDF; Fulltext from publisher: PDF; Related data file(s): ZIP; Supplementary information: ZIP;