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2018-03-29
17:40
Search for the Standard Model Higgs Boson at LEP /DELPHI Collaboration ; ALEPH Collaboration ; L3 Collaboration ; OPAL Collaboration
The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have collected 2461 pb−1 of e+e− collision data at centre-of-mass energies between 189 and 209 GeV, of which 536 pb−1 have energies above 206 GeV. The data have been used to search for the Standard Model Higgs boson. [...]
CERN-ALEPH-2002-024; CERN-ALEPH-CONF-2002-013; DELPHI-2002-088-CONF-621; CERN-DELPHI-2002-088-CONF-621; L3-Note-2766; OPAL-TN721; LHWG-Note-2002-01.- Geneva : CERN, 2002 - 28 p. Fulltext: cer-002264432 - PDF; aleph-2002-024 - PDF;
In : 31st International Conference on High Energy Physics, Amsterdam, The Netherlands, 25 - 31 Jul 2002

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2018-01-08
14:52
First measurement of the $CP$-violating phase $\phi_s^{d\overline{d}}$ in $B_s^0\to(K^+\pi^-)(K^-\pi^+)$ decays / LHCb Collaboration
A flavour-tagged decay-time-dependent amplitude analysis of $B_s^0\to(K^+\pi^-)(K^-\pi^+)$ decays is presented in the $K^{\pm}\pi^{\mp}$ mass range from 750 to 1600 MeV$/c^2$. The analysis uses $pp$ collision data collected with the LHCb detector at centre-of-mass energies of $7$ and $8$ TeV, corresponding to an integrated luminosity of $3.0$ fb$^{-1}$. [...]
LHCB-PAPER-2017-048; CERN-EP-2017-320; arXiv:1712.08683.- Geneva : CERN, 2018-03-23 - 33 p. - Published in : JHEP 03 (2018) 140 Article from SCOAP3: PDF; Fulltext: PDF; Preprint: PDF; Related data file(s): ZIP; Supplementary information: ZIP;

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2017-12-22
09:56
Search for weakly decaying $b$-flavored pentaquarks / LHCb Collaboration
Investigations of the existence of pentaquark states containing a single $b$ (anti)quark decaying weakly into four specific final states J/$\psi K^+\pi^- p$, J/$\psi K^- \pi^- p$, J/$\psi K^- \pi^+ p$, and $J/\psi \phi (1020) p$ are reported. The data sample corresponds to an integrated luminosity of 3.0/fb in 7 and 8 TeV pp collisions acquired with the LHCb detector. [...]
CERN-EP-2017-329; LHCB-PAPER-2017-043; arXiv:1712.08086; LHCB-PAPER-2017-043.- Geneva : CERN, 2018-02-17 - 11 p. - Published in : Phys. Rev. D 97 (2018) 032010 Article from SCOAP3: PDF; Preprint: PDF; Related data file(s): ZIP;

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2017-12-21
15:21
Measurement of $CP$ asymmetry in $B_s^0 \to D_s^{\mp} K^{\pm}$ decays / LHCb Collaboration
We report the measurements of the $CP$-violating parameters in $B_s^0 \to D_s^{\mp} K^{\pm}$ decays observed in $pp$ collisions, using a data set corresponding to an integrated luminosity of $3.0\,\text{fb}^{-1}$ recorded with the LHCb detector. We measure $C_f = 0.73 \pm 0.14 \pm 0.05$, $A^{\Delta \Gamma}_f = 0.39 \pm 0.28 \pm 0.15$, $A^{\Delta \Gamma}_{\overline{f}} = 0.31 \pm 0.28 \pm 0.15$, $S_f = -0.52 \pm 0.20 \pm 0.07$, $S_{\overline{f}} = -0.49 \pm 0.20 \pm 0.07$, where the uncertainties are statistical and systematic, respectively. [...]
LHCB-PAPER-2017-047; CERN-EP-2017-315; arXiv:1712.07428; LHCB-PAPER-2017-047.- Geneva : CERN, 2018-03-12 - 28 p. - Published in : JHEP 03 (2018) 059 Preprint: PDF; Related data file(s): ZIP; Supplementary information: ZIP;

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2017-11-21
11:13
Search for excited $B_c^+$ states / LHCb Collaboration
A search is performed in the invariant mass spectrum of the $B_c^{+}\pi^{+}\pi^{-}$ system for the excited $B_c^{+}$ states $B_c(2^{1}S_{0})^+$ and $B_c(2^{3}S_{1})^+$ using a data sample of $pp$ collisions collected by the LHCb experiment at the centre-of-mass energy of $\sqrt{s} = 8 \,{\mathrm{TeV}}$, corresponding to an integrated luminosity of $2 \,{\mathrm{fb^{-1}}}$. No evidence is seen for either state. [...]
CERN-EP-2017-306; LHCB-PAPER-2017-042; arXiv:1712.04094; LHCB-PAPER-2017-042.- Geneva : CERN, 2018-01-29 - 19 p. - Published in : JHEP 01 (2018) 138 Article from SCOAP3: PDF; Preprint: PDF; Supplementary information: ZIP; External link: Additional information for the analysis

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2017-11-20
16:12
Updated determination of $D^0$-$\overline{D}{}^0$ mixing and CP violation parameters with $D^0\to K^+\pi^-$ decays / LHCb Collaboration
We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of $D^0\to K^+\pi^-$ to $D^0\to K^-\pi^+$ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of $5.0$ fb$^{-1}$ recorded by the LHCb experiment from 2011 through 2016. [...]
CERN-EP-2017-304; LHCB-PAPER-2017-046; arXiv:1712.03220; LHCB-PAPER-2017-046.- Geneva : CERN, 2018-02-23 - 11 p. - Published in : Phys. Rev. D 97 (2018) 031101 Article from SCOAP3: PDF; Preprint: PDF; Related data file(s): ZIP; Supplementary information: ZIP;

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2017-11-20
10:26
Measurement of branching fractions of charmless four-body $\Lambda_b^0$ and $\Xi_b^0$ decays / LHCb Collaboration
A search for charmless four-body decays of $\Lambda_{b}^{0}$ and $\Xi_{b}^{0}$ baryons with a proton and three charged mesons (either kaons or pions) in the final state is performed. The data sample used was recorded in 2011 and 2012 with the LHCb experiment and corresponds to an integrated luminosity of 3 fb$^{-1}$. [...]
CERN-EP-2017-278; LHCB-PAPER-2017-034; arXiv:1711.05490; CERN-EP-2017-278-LHCB-PAPER-2017-034; LHCB-PAPER-2017-034.- Geneva : CERN, 2018-02-16 - 25 p. - Published in : JHEP 02 (2018) 098 Article from SCOAP3: PDF; Preprint: PDF; Related data file(s): ZIP;

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2017-11-16
16:44
Measurement of the ratio of branching fractions $\mathcal{B}(B_c^+\,\to\,J/\psi\tau^+\nu_\tau)$/$\mathcal{B}(B_c^+\,\to\,J/\psi\mu^+\nu_\mu)$ / LHCb Collaboration
A measurement is reported of the ratio of branching fractions $\mathcal{R}(J/\psi)=\mathcal{B}(B_c^+\,\to\,J/\psi\tau^+\nu_\tau)/\mathcal{B}(B_c^+\,\to\,J/\psi \mu^+\nu_\mu)$, where the $\tau^+$ lepton is identified in the decay mode $\tau^+\,\to\,\mu^+\nu_\mu\overline{\nu}_\tau$. This analysis uses a sample of proton-proton collision data corresponding to 3.0$\mathrm{\,fb}^{-1}$ of integrated luminosity recorded with the LHCb experiment at center-of-mass energies $7\,\mathrm{TeV}$ and $8\,\mathrm{TeV}$. [...]
LHCB-PAPER-2017-035; CERN-EP-2017-275; arXiv:1711.05623; LHCB-PAPER-2017-035.- Geneva : CERN, 2018-03-27 - 10 p. - Published in : Phys. Rev. Lett. 120 (2018) 121801 Article from SCOAP3: PDF; Preprint: PDF; Related data file(s): ZIP; Supplementary information: ZIP;

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2017-11-16
09:10
First observation of $B^{+} \to D_s^{+}K^{+}K^{-}$ decays and a search for $B^{+} \to D_s^{+}\phi$ decays / LHCb Collaboration
A search for $B^{+} \to D_s^{+}K^{+}K^{-}$ decays is performed using $pp$ collision data corresponding to an integrated luminosity of 4.8 fb$^{-1}$, collected at centre-of-mass energies of 7, 8 and 13$\,$TeV with the LHCb experiment. A significant signal is observed for the first time and the branching fraction is determined to be \begin{equation*} \mathcal{B}(B^{+} \to D_s^{+}K^{+}K^{-} ) = (7.1 \pm 0.5 \pm 0.6 \pm 0.7) \times 10^{-6}, \end{equation*} where the first uncertainty is statistical, the second systematic and the third due to the uncertainty on the branching fraction of the normalisation mode $B^{+} \to D_s^{+} \overline{\kern -0.2em D}^{0}$. [...]
LHCB-PAPER-2017-032; CERN-EP-2017-289; arXiv:1711.05637; LHCB-PAPER-2017-032.- Geneva : CERN, 2018-01-26 - 22 p. - Published in : JHEP 01 (2018) 131 Article from SCOAP3: PDF; Preprint: PDF; Related data file(s): ZIP;

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2017-11-03
16:04
Measurements of the branching fractions of $\Lambda_{c}^{+} \rightarrow p \pi^{-} \pi^{+}$, $\Lambda_{c}^{+} \rightarrow p K^{-} K^{+}$, and $\Lambda_{c}^{+} \rightarrow p \pi^{-} K^{+}$ / LHCb Collaboration
The ratios of the branching fractions of the decays $\Lambda_{c}^{+} \rightarrow p \pi^{-} \pi^{+}$, $\Lambda_{c}^{+} \rightarrow p K^{-} K^{+}$, and $\Lambda_{c}^{+} \rightarrow p \pi^{-} K^{+}$ with respect to the Cabibbo-favoured $\Lambda_{c}^{+} \rightarrow p K^{-} \pi^{+}$ decay are measured using proton-proton collision data collected with the LHCb experiment at a 7 TeV centre-of-mass energy and corresponding to an integrated luminosity of 1.0 fb$^{-1}$: \begin{align*} \frac{\mathcal{B}(\Lambda_{c}^{+} \rightarrow p \pi^{-} \pi^{+})}{\mathcal{B}(\Lambda_{c}^{+} \rightarrow p K^{-} \pi^{+})} & = (7.44 \pm 0.08 \pm 0.18)\,\%, \\ \frac{\mathcal{B}(\Lambda_{c}^{+} \rightarrow p K^{-} K^{+})}{\mathcal{B}(\Lambda_{c}^{+} \rightarrow p K^{-} \pi^{+})} &= (1.70 \pm 0.03 \pm 0.03)\,\%, \\ \frac{\mathcal{B}(\Lambda_{c}^{+} \rightarrow p \pi^{-} K^{+})}{\mathcal{B}(\Lambda_{c}^{+} \rightarrow p K^{-} \pi^{+})} & = (0.165 \pm 0.015 \pm 0.005 )\,\%, \end{align*} where the uncertainties are statistical and systematic, respectively. These results are the most precise measurements of these quantities to date. [...]
CERN-EP-2017-247; LHCB-PAPER-2017-026; arXiv:1711.01157; LHCB-PAPER-2017-026.- Geneva : CERN, 2018-03-08 - 22 p. - Published in : JHEP 03 (2018) 043 Article from SCOAP3: PDF; Preprint: PDF; Related data file(s): ZIP;

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