Mostrando ítems 221-240 de 538

    • Determination of γ and −2βs from charmless two-body decays of beauty mesons 

      Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physics Letters B , 2015, Vol. 741 (Febrer), 2015-02-04)
      Using the latest LHCb measurements of time-dependent CP violation in the B-s(0) -> K+K- decay, a U-spin relation between the decay amplitudes of B-s(0) -> K+K- and B-0 -> p(+)p(-) decay processes allows ...
    • Measurement of the B 0 s  → ϕϕ branching fraction and search for the decay B 0 → ϕϕ 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.8 (Octubre), 2015-10-08)
      Using a dataset corresponding to an integrated luminosity of 3.0 fb−1 collected in pp collisions at centre-of-mass energies of 7 and 8 TeV, the B 0 s  → ϕϕ branching fraction is measured to be B(B0s→ϕ ...
    • Measurement of the CP-violating phase β in B0 → J/ψ π+ π− decays and límits on penguin effects 

      Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physics Letters B , 2015, Vol. 742, (Març), 2015-03-06)
      Time-dependent CPviolation is measured in the (—)B0→J/ψπ+π−channel for each π+π−resonant final state using data collected with an integrated luminosity of 3.0fb−1in ppcollisions using the LHCb detector. ...
    • Low noise front end ICECAL ASIC for the upgrade of the LHCb calorimeter 

      Abellan Beteta, Carlos; Vilasís Cardona, Xavier (Journal of Instrumentation, 2012, Vol. 7, No.1 (Gener), 2012-01-23)
      A fully differential ASIC with cooled input termination is presented as a solution for the Upgrade of the Calorimeter front end electronics. The LHCb experiment needs to increase about ten times the ...
    • Measurement of the time-integrated CP asymmetry in D 0 → K 0S K 0S decays 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.10 (Octubre), 2015-10-08)
      The time-integrated CP asymmetry in the decay D 0 → K 0S K 0S is measured using 3 fb−1 of proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The ...
    • Measurement of the exclusive Υ production cross-section in pp collisions at s√=7 TeV and 8 TeV 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.9 (Setembre), 2015-09-14)
      A study is presented of central exclusive production of Υ(nS) states, where the Υ(nS) resonances decay to the μ + μ − final state, using pp collision data recorded by the LHCb experiment. The cross-section ...
    • Measurement of CP violation parameters and polarisation fractions in B0s→J/ψK¯¯¯¯∗0 decays 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.11 (Novembre), 2015-11-12)
      The first measurement of CP asymmetries in the decay B0s→J/ψK¯¯¯¯∗(892)0 and an updated measurement of its branching fraction and polarisation fractions are presented. The results are obtained using ...
    • Measurements of the B +, B 0, B0s meson and Λ0b baryon lifetimes 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2014, Vol. 2014, No.a (Abril), 2014-04-16)
      Measurements of b-hadron lifetimes are reported using pp collision data, corresponding to an integrated luminosity of 1.0 fb−1, collected by the LHCb detector at a centre-of-mass energy of 7 TeV. Using ...
    • Observation of Z production in proton-lead collisions at LHCb 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2014, Vol. 2014, No.8 (Agost), 2014-08-19)
      The first observation of Z boson production in proton-lead collisions at a centre-of-mass energy per proton-nucleon pair of sNN−−−−√ = 5 TeV is presented. The data sample corresponds to an integrated ...
    • Searches for Λ0b and Ξ0b decays to K0Spπ− and K0SpK− final states with first observation of the Λ0b→K0Spπ− decay 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2014, Vol. 2014, No.4 (Abril), 2014-04-11)
      A search for previously unobserved decays of beauty baryons to the final states K0Spπ− and K0SpK− is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 ...
    • Measurement of theB± production cross-section in pp collisions at √s= 7TeV 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2012, Vol. 2012, No.4 (Abril), 2012-04-19)
      The production of B ± mesons in proton-proton collisions at s√ = 7 TeV is studied using 35 pb−1 of data collected by the LHCb detector. The B ± mesons are reconstructed exclusively in the B ± → J/ψK ± ...
    • Study of forward Z + jet production in pp collisions at s√ = 7 TeV 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2014, Vol. 2014, No.1 (Gener), 2014-01-09)
      A measurement of the Z(→ μ + μ −) + jet production cross-section in pp collisions at a centre-of-mass energy s√ = 7 TeV is presented. The analysis is based on an integrated luminosity of 1.0 fb−1 recorded ...
    • First observation and measurement of the branching fraction for the decay B 0 s  → D ∗ s ∓ K ± 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.6 (Juny), 2015-06-18)
      The first observation of the B 0 s  → D ∗ s ∓ K ± decay is reported using 3.0 fb−1 of proton-proton collision data collected by the LHCb experiment. The D ∗ s ∓ mesons are reconstructed through the decay ...
    • Measurement of the time-dependent CP asymmetries in B 0s  → J/ψK 0S 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.6 (Juny), 2015-06-18)
    • Precise measurements of the properties of the B1(5721)0,+ and B *2 (5747)0,+ states and observation of B+,0π−,+ mass structures 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.4 (Abril), 2015-04-07)
      Invariant mass distributions of B+π− and B0π+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fb−1 of pp collision data, ...
    • Measurement of the forward-backward asymmetry in Z/γ∗ → μ + μ − decays and determination of the effective weak mixing angle 

      Badalov, Alexey; Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Journal of High Energy Physics, 2015, Vol. 2015, No.11 (Noviembre), 2015-11-27)
      The forward-backward charge asymmetry for the process qq¯¯→Z/γ∗→μ+μ− is measured as a function of the invariant mass of the dimuon system. Measurements are performed using proton proton collision data ...
    • Angular analysis of charged and neutral B → Kμ + μ − decays 

      Badalov, Alexey; Calvo Gómez, Míriam; Camboni, Alessandro; LHCb Collaboration - CERN (Journal of High Energy Physics, 2014, Vol. 2014, No.5 (Maig), 2014-05-19)
      The angular distributions of the rare decays B + → K + μ + μ − and B0→K0Sμ+μ− are studied with data corresponding to 3fb−1 of integrated luminosity, collected in proton-proton collisions at 7 and 8 TeV ...
    • Measurement of ϒ production in pp collisions at s−−√=7 TeV 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (The European Physical Journal C, 2012. Vol. 72, No. 6 (Juny), 2012-06-07)
      The production of ϒ(1S), ϒ(2S) and ϒ(3S) mesons in proton-proton collisions at the centre-of-mass energy of s√=7 TeV is studied with the LHCb detector. The analysis is based on a data sample of 25 pb−1 ...
    • Search for CP violation in D0 → π− π+ π0 decays with the energy test 

      Calvo Gómez, Míriam; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physics Letters B , 2015, Vol. 740, (Gener), 2015-01-05)
      A search for time-integrated CP violation in the Cabibbo-suppressed decay D-0 -> pi(-)pi(+)pi(0) ir is performed using for the first time an unbinned model-independent technique known as the energy test. ...
    • Search for CP violation in the decay D+→π−π+π+ 

      Calvo Gómez, Míriam; Camboni, Alessandro; Vilasís Cardona, Xavier; LHCb Collaboration - CERN (Physics Letters B , 2014, Vol. 728, (Gener), 2014-01-20)
      A search for CP violation in the phase space of the decay $D^+\to\pi^-\pi^+\pi^+$ is reported using $pp$ collision data, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected by the LHCb ...