# PH-EP Articles

Последние добавления:
2014-10-21
20:08
 Measurement of the ratio $\mathcal{B}( \mathrm{B_c^+} \rightarrow \mathrm{J}/\psi\, \pi^+ \pi^+ \pi^-)/\mathcal{B}( \mathrm{B_c^+} \rightarrow \mathrm{J}/\psi\, \pi^+)$ and the production cross sections times branching fractions of $\mathrm{ B_c^+} \rightarrow \mathrm{J}/\psi\, \pi^+$ and $\mathrm{ B^+} \rightarrow \mathrm{J}/\psi\, \mathrm{K}^+$ in pp collisions at $\sqrt{s}$ = 7 TeV / CMS Collaboration The $\mathrm{B_c^+} \rightarrow \mathrm{J}/\psi\, \pi^+$ and $\mathrm{B_c^+} \rightarrow \mathrm{J}/\psi\, \pi^+ \pi^+ \pi^-$ decay modes are studied in proton-proton collisions at a center-of-mass energy of $7~\mathrm{TeV}$ with the CMS detector at the LHC. The kinematic region investigated requires $\mathrm{B_c^+}$ mesons with transverse momentum $p_{\mathrm{T}}$ greater than $15~\mathrm{GeV}$ and rapidity $|y|$ lower than $1.6$. [...] arXiv:1410.5729; CMS-BPH-12-011; CERN-PH-EP-2014-248.- Geneva : CERN, 2015 - 29 p. - Published in : J. High Energy Phys. 01 (2015) 063 Fulltext: PDF; External link: Preprint

2014-10-16
15:39
 Identification techniques for highly boosted W bosons that decay into hadrons / CMS Collaboration In searches for new physics in the energy regime of the LHC, it is becoming increasingly important to distinguish single-jet objects that originate from the merging of the decay products of W bosons produced with high transverse momenta from jets initiated by single partons. Algorithms are defined to identify such W jets for different signals of interest, using techniques that are also applicable to other decays of bosons to hadrons that result in a single jet, such as those from highly boosted Z and Higgs bosons. [...] arXiv:1410.4227; CMS-JME-13-006; CERN-PH-EP-2014-241.- Geneva : CERN, 2014 - 43 p. - Published in : J. High Energy Phys. 12 (2014) 017 Fulltext: PDF; Springer Open Access article: PDF; External link: Preprint

2014-10-16
15:13
 Search for $CP$ violation in $D^0\to \pi^-\pi^+\pi^0$ decays with the energy test / LHCb Collaboration A search for time-integrated CP violation in the Cabibbo-suppressed decay $D^0\to\pi^-\pi^+\pi^0$ is performed using for the first time an unbinned model-independent technique known as the energy test. Using proton-proton collision data, corresponding to an integrated luminosity of 2.0 fb$^{-1}$ collected by the LHCb detector at a centre-of-mass energy of $\sqrt{s}$ = 8 TeV, the world's best sensitivity to CP violation in this decay is obtained [...] arXiv:1410.4170; LHCB-PAPER-2014-054; CERN-PH-EP-2014-251.- Geneva : CERN, 2015 - 16 p. - Published in : Phys. Lett. B 740 (2015) 158 Fulltext: PDF; Related data file(s): ZIP; Related supplementary data file(s): ZIP; External link: Preprint

2014-10-16
14:23
 Search for the $X_b$ and other hidden-beauty states in the $\pi^+ \pi^- \Upsilon(1 \rm S)$ channel at ATLAS / ATLAS Collaboration This Letter presents a search for a hidden-beauty counterpart of the $X(3872)$ in the mass ranges 10.05--10.31 GeV and 10.40--11.00 GeV, in the channel $X_b \to \pi^{+} \pi^{-} \Upsilon(1 \rm S)(\rightarrow\mu^+\mu^-)$, using 16.2 fb$^{-1}$ of $\sqrt{s}=8$ TeV $pp$ collision data collected by the ATLAS detector at the LHC. No evidence for new narrow states is found, and upper limits are set on the product of the $X_b$ cross section and branching fraction, relative to those of the $\Upsilon(2 \rm S)$, at the 95% confidence level using the CL$_S$ approach. [...] CERN-PH-EP-2014-230; arXiv:1410.4409.- Geneva : CERN, 2015 - 8 p. - Published in : Phys. Lett. B 74 (2015) 199-217 Fulltext: PDF; External links: Previous draft version; Preprint

2014-10-10
15:29
 Searches for heavy scalar and pseudoscalar Higgs bosons and for flavor-violating decays of the top quark into a Higgs boson in $\mathrm{p}\mathrm{p}$ collisions at $\sqrt{s}$ = 8 TeV / CMS Collaboration Searches are presented for heavy scalar ($\mathrm{H}$) and pseudoscalar ($\mathrm{A}$) Higgs bosons posited in the two doublet model (2HDM) extensions of the standard model (SM). These searches are based on a data sample of $\mathrm{p}\mathrm{p}$ collisions collected with the CMS experiment at the LHC at a center-of-mass energy of $\sqrt{s} = 8~\mathrm{TeV}$ and corresponding to an integrated luminosity of $19.5~\mathrm{fb}^{-1}$. [...] arXiv:1410.2751; CMS-HIG-13-025; CERN-PH-EP-2014-239.- Geneva : CERN, 2014 - 35 p. - Published in : Phys. Rev. D 90 (2014) 112013 Fulltext: PDF; External link: Preprint

2014-10-09
08:27
 Production of inclusive $\Upsilon$(1S) and $\Upsilon$(2S) in p-Pb collisions at $\mathbf{\sqrt{s_{{\rm NN}}} = 5.02}$ TeV / ALICE Collaboration We report on the production of inclusive $\Upsilon$(1S) and $\Upsilon$(2S) in p-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV at the LHC. The measurement is performed with the ALICE detector at backward ($-4.46< y_{{\rm cms}}<-2.96$) and forward ($2.03< y_{{\rm cms}}<3.53$) rapidity down to zero transverse momentum. [...] arXiv:1410.2234; CERN-PH-EP-2014-196.- Geneva : CERN, 2015 - 24 p. - Published in : Phys. Lett. B 740 (2015) 105-117 Fulltext: PDF; External link: Preprint

2014-10-08
11:02
 Measurement of prompt $\psi(2\mathrm{S})$ to $\mathrm{J}/\psi$ yield ratios in $\mathrm{Pb}\mathrm{Pb}$ and $\mathrm{p}\mathrm{p}$ collisions at $\sqrt{s_\mathrm{NN}} = 2.76~\mathrm{TeV}$ / CMS Collaboration The ratio between the prompt $\psi(2\mathrm{S})$ and $\mathrm{J}/\psi$ yields, reconstructed via their decays into $\mu^+\mu^-$, is measured in $\mathrm{Pb}\mathrm{Pb}$ and $\mathrm{p}\mathrm{p}$ collisions at $\sqrt{s_\mathrm{NN}} = 2.76~\mathrm{TeV}$. The analysis is based on $\mathrm{Pb}\mathrm{Pb}$ and $\mathrm{p}\mathrm{p}$ data samples collected by CMS at the LHC, corresponding to integrated luminosities of $150~\mu\mathrm{b}^{-1}$ and $5.4~\mathrm{pb}^{-1}$, respectively. [...] arXiv:1410.1804; CMS-HIN-12-007; CERN-PH-EP-2014-240.- Geneva : CERN, 2014 - 27 p. - Published in : Phys. Rev. Lett. 113 (2014) 262301 Fulltext: PDF; External link: Preprint

2014-10-05
15:59
 Measurement of the W boson helicity in events with a single reconstructed top quark in pp collisions at $\sqrt{s}$ = 8 TeV / CMS Collaboration A measurement of the W boson helicity is presented, where the W boson originates from the decay of a top quark produced in pp collisions. The event selection, optimized for reconstructing a single top quark in the final state, requires exactly one isolated lepton (muon or electron) and exactly two jets, one of which is likely to originate from the hadronization of a bottom quark. [...] arXiv:1410.1154; CMS-TOP-12-020; CERN-PH-EP-2014-242.- Geneva : CERN, 2015 - 33 p. - Published in : J. High Energy Phys. 01 (2015) 053 Fulltext: PDF; Springer Open Access article: PDF; External link: Preprint

2014-10-02
07:58
 Precision luminosity measurements at LHCb / LHCb collaboration Measuring cross-sections at the LHC requires the luminosity to be determined accurately at each centre-of-mass energy $\sqrt{s}$. In this paper results are reported from the luminosity calibrations carried out at the LHC interaction point 8 with the LHCb detector for $\sqrt{s}$ = 2.76, 7 and 8 TeV (proton-proton collisions) and for $\sqrt{s_{NN}}$ = 5 TeV (proton-lead collisions). [...] arXiv:1410.0149; LHCB-PAPER-2014-047; CERN-PH-EP-2014-221.- Geneva : CERN, 2014 - 99 p. - Published in : J. Instrum. 9 (2014) P12005 Fulltext: PDF; IOP Open Access article: PDF; Related data file(s): ZIP; Related supplementary data file(s): ZIP; External link: Preprint

2014-10-02
07:58
 Precision measurement of the mass and lifetime of the $\Xi_b^-$ baryon / LHCb collaboration We report on measurements of the mass and lifetime of the $\Xi_b^-$ baryon using about 1800 $\Xi_b^-$ decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0 fb$^{-1}$ collected by the LHCb experiment. The decays are reconstructed in the $\Xi_b^-\to\Xi_c^0\pi^-$, $\Xi_c^0\to pK^-K^-\pi^+$ channel and the mass and lifetime are measured using the $\Lambda_b^0\to\Lambda_c^+\pi^-$ mode as a reference. [...] arXiv:1409.8568; LHCB-PAPER-2014-048; CERN-PH-EP-2014-226.- Geneva : CERN, 2014 - 7 p. - Published in : Phys. Rev. Lett. 113 (2014) 242002 Fulltext: PDF; Related data file(s): ZIP; Related supplementary data file(s): ZIP; External link: Preprint