Articles publicats en revistes: Recent submissions

Now showing items 341-360 of 546

    • Precision Measurement of the Mass and Lifetime of the Ξ0b Baryon 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 113, No. 3 (Juliol), 2014-07-15)
      Using a proton-proton collision data sample corresponding to an integrated luminosity of 3  fb−1 collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 Ξ0b→Ξ+cπ−, Ξ+c→pK−π+ signal decays ...

    • Observation of Photon Polarization in the b→sγ Transition 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 112, No. 16 (Abril), 2014-04-22)
      This Letter presents a study of the flavor-changing neutral current radiative B±→K±π∓π±γ decays performed using data collected in proton-proton collisions with the LHCb detector at 7 and 8 TeV center-of-mass ...

    • Measurement of CP Violation in B0→J/ψK0S Decays 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2015, Vol. 115, No. 3 (Juliol), 2015-07-14)
      Measurements are presented of the CP violation observables S and C in the decays of B0 and ¯B0 mesons to the J/ψK0S final state. The data sample corresponds to an integrated luminosity of 3.0  fb−1 ...

    • First Measurement of the Charge Asymmetry in Beauty-Quark Pair Production 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 113, No. 8 (Agosto), 2014-08-20)
      The difference in the angular distributions between beauty quarks and antiquarks, referred to as the charge asymmetry, is measured for the first time in b¯b pair production at a hadron collider. The ...

    • Test of Lepton Universality Using B+→K+ℓ+ℓ− Decays 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 113, No. 15 (Octubre), 2014-10-06)
      A measurement of the ratio of the branching fractions of the B+→K+μ+μ− and B+→K+e+e− decays is presented using proton-proton collision data, corresponding to an integrated luminosity of 3.0  fb−1, ...

    • Observation of the Resonant Character of the Z(4430)− State 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 112, No. 22 (Juny), 2014-06-04)
      Resonant structures in B0→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 the LHCb detector. The ...

    • First Observation of the Decay B∗s2(5840)0→B*+K− and Studies of Excited B0s Mesons 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2013, Vol. 110, No. 15 (Abril), 2013-04-09)
      The properties of the orbitally excited (L=1) B0s states are studied by using 1.0  fb−1 of pp collisions at √s=7  TeV collected with the LHCb detector. The first observation of the B∗s2(5840)0 meson ...

    • Evidence for CP Violation in B+→p¯pK+ Decays 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 113, No. 14 (Octubre), 2014-09-20)
      Three-body B+→p¯pK+ and B+→p¯pπ+ decays are studied using a data sample corresponding to an integrated luminosity of 3.0  fb−1 collected by the LHCb experiment in proton-proton collisions at center-of-mass ...

    • First Measurement of the CP-Violating Phase in B0s→ϕϕ Decays 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2013, Vol. 110, No. 24 (Juny), 2013-06-12)
      A first flavor-tagged measurement of the time-dependent CP-violating asymmetry in B0s→ϕϕ decays is presented. In this decay channel, the CP-violating weak phase arises due to CP violation in the ...

    • Observation of Excited Λ0b Baryons 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2012, Vol. 109, No. 7 (Octubre), 2012-10-26)
      Using pp collision data corresponding to 1.0  fb−1 integrated luminosity collected by the LHCb detector, two narrow states are observed in the Λ0bπ+π− spectrum with masses 5911.97±0.12(stat)±0.02(syst ...

    • Determination of the X(3872) Meson Quantum Numbers 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2013, Vol. 110, No. 22 (Maig), 2013-05-29)
      The quantum numbers of the X(3872) meson are determined to be JPC=1++ based on angular correlations in B+→X(3872)K+ decays, where X(3872)→π+π−J/ψ and J/ψ→μ+μ−. The data correspond to 1.0  fb−1 of pp ...

    • Measurement of the ¯B0s→D−sD+s and ¯B0s→D−D+s Effective Lifetimes 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2014, Vol. 112, No. 11 (Març), 2014-03-19)
      The first measurement of the effective lifetime of the ¯B0s meson in the decay ¯B0s→D−sD+s is reported using a proton-proton collision data set, corresponding to an integrated luminosity of 3  fb−1, ...

    • Observation of B0→¯¯¯D0K+K− and Evidence for B0s→¯¯¯D0K+K− 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2012, Vol. 109, No. 13 (Setembre), 2012-09-26)
      The first observation of the decay B0→¯¯¯D0K+K− is reported from an analysis of 0.62  fb−1 of pp collision data collected with the LHCb detector. Its branching fraction is measured relative to that of ...

    • Observation of a Resonance in B+→K+μ+μ− Decays at Low Recoil 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2013, Vol. 111, No. 11 (Setembre), 2013-09-10)
      A broad peaking structure is observed in the dimuon spectrum of B+→K+μ+μ− decays in the kinematic region where the kaon has a low recoil against the dimuon system. The structure is consistent with ...

    • Observation of the B0s→η′η′ Decay 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2015, Vol. 115, No. 5 (Juliol), 2015-07-28)
      The first observation of the B0s→η′η′ decay is reported. The study is based on a sample of proton-proton collisions corresponding to 3.0  fb−1 of integrated luminosity collected with the LHCb detector. ...

    • Measurement of the Ratio of Branching Fractions B(¯B0→D*+τ−¯ντ)/B(¯B0→D*+μ−¯νμ) 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2015, Vol. 115, No. 11 (Setembre), 2015-09-09)
      The branching fraction ratio R(D∗)≡B(¯B0→D*+τ−¯ντ)/B(¯B0→D*+μ−¯νμ) is measured using a sample of proton-proton collision data corresponding to 3.0  fb−1 of integrated luminosity recorded by the LHCb ...

    • First Observation of Top Quark Production in the Forward Region 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2015, Vol. 115, No. 11 (Setembre), 2015-09-08)
      Top quark production in the forward region in proton-proton collisions is observed for the first time. The W+b final state with W→μν is reconstructed using muons with a transverse momentum, pT, larger ...

    • First Evidence for the Decay B0s→μ+μ− 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2013, Vol. 110, No. 2 (Gener), 2013-01-07)
      A search for the rare decays B0s→μ+μ− and B0→μ+μ− is performed with data collected in 2011 and 2012 with the LHCb experiment at the Large Hadron Collider. The data samples comprise 1.1  fb−1 of proton-proton ...

    • Observation of B(s)(0) → J/ψf(2)'(1525) in J/ψK+ K- final states 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2012, Vol. 108, No. 15 (Abril), 2012-04-09)
      The decay ¯¯¯B0s→J/ψK+K− is investigated using 0.16  fb−1 of data collected with the LHCb detector using 7 TeV pp collisions. Although the J/ψϕ channel is well known, final states at higher K+K− masses ...

    • Evidence for CP Violation in Time-Integrated D0→h−h+ Decay Rates 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physical Review Letters, 2012, Vol. 108, No. 11 (Març), 2012-03-12)
      A search for time-integrated CP violation in D0→h−h+ (h=K, π) decays is presented using 0.62  fb−1 of data collected by LHCb in 2011. The flavor of the charm meson is determined by the charge of the ...