Listando Recerca por materia "53"
Mostrando ítems 61-80 de 96
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Observation of a Resonance in B+→K+μ+μ− Decays at Low Recoil
(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 B(s)(0) → J/ψf(2)'(1525) in J/ψK+ K- final states
(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 ... -
Observation of B0→¯¯¯D0K+K− and Evidence for B0s→¯¯¯D0K+K−
(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 CP violation in B ± → D K ± decays
(Physics Letters B, 2012, Vol. 712, No. 3 (Juny), 2012-06-06)An analysis of B+ to DK+ and B+ to Dpi+ decays is presented where the D meson is reconstructed in the two-body final states: K+pi-, K+K-, pi+pi- and pi+K-. Using 1.0 fb-1 of LHCb data, measurements of ... -
Observation of D0−¯¯¯D0 Oscillations
(Physical Review Letters, 2013, Vol. 110, No. 10 (Març), 2013-03-05)We report a measurement of the time-dependent ratio of D0→K+π− to D0→K−π+ decay rates in D*+-tagged events using 1.0 fb−1 of integrated luminosity recorded by the LHCb experiment. We measure the mixing ... -
Observation of J/ψ-pair production in pp collisions at s=7 TeV
(Physics Letters B, Vol. 707, No. 1 (Gener 2012), 2012-01-16)The production of J/ψpairs in proton–proton collisions at a centre-of-mass energy of 7 TeV has beenobserved using an integrated luminosity of 37.5 pb−1collected with the LHCb detector. The productionc ... -
Observation of J/ψp Resonances Consistent with Pentaquark States in Λ0b→J/ψK−p Decays
(Physical Review Letters, 2015, Vol. 115, No. 7 (Agost), 2015-08-12)Observations of exotic structures in the J/ψp channel, which we refer to as charmonium-pentaquark states, in Λ0b→J/ψK−p decays are presented. The data sample corresponds to an integrated luminosity of ... -
Observation of Overlapping Spin-1 and Spin-3 ¯D0K− Resonances at Mass 2.86 GeV/c2
(Physical Review Letters, 2014, Vol. 113, No. 16 (Octubre), 2014-10-14)The resonant substructure of B0s→¯D0K−π+ decays is studied using a data sample corresponding to an integrated luminosity of 3.0 fb−1 of pp collision data recorded by the LHCb detector. An excess at ... -
Observation of Photon Polarization in the b→sγ Transition
(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 ... -
Observation of the B0s→η′η′ Decay
(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. ... -
Observation of the decay B+c → ψ(2S)π+
(Physical Review D, 2013, Vol. 87 , No.7 (Abril), 2013-04-26)The decay B+c→ψ(2S)π+ with ψ(2S)→μ+μ− is observed with a significance of 5.2σ using pp collision data corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experiment. The branching ... -
Observation of the decay B0s → ψ(2S) K+ π−
(Physics Letters B , 2015, Vol. 747, (Juliol), 2015-07-30)The decay B-0s → ψ(2S)K+π- is observed using a data set corresponding to an integrated luminosity of 3.0fb-1 collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8 TeV. ... -
Observation of the decay B0s→D0φ
(Physics Letters B, 2013, Vol. 727, No. 4-5 (Desembre 2013), 2013-12)First observation of the decayB0s→D0φis reported usingppcollision data, corresponding to an inte-grated luminosity of 1.0 fb−1, collected by the LHCb experiment at a centre-of-mass energy of 7 TeV. ... -
Observation of the Resonant Character of the Z(4430)− State
(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 ... -
Observation of the suppressed ADS modes B± → [π± K∓ π+ π−] DK± and B± → [π± K∓ π+ π−] Dπ
(Physics Letters B, 2013, Vol. 723, No. 1-3 (Juny), 2013-06-10)An analysis of B±→DK±B±→DK± and B±→Dπ±B±→Dπ± decays is presented where the D meson is reconstructed in the four-body final state K±π∓π+π−K±π∓π+π−. Using LHCb data corresponding to an integrated luminosity ... -
Observation of ¯B0(s)→J/ψ f1(1285) Decays and Measurement of the f1(1285) Mixing Angle
(Physical Review Letters, 2014, Vol. 112, No. 9 (Març), 2014-03-04)Decays of ¯B0s and ¯B0 mesons into J/ψ π+π−π+π− final states, produced in pp collisions at the LHC, are investigated using data corresponding to an integrated luminosity of 3 fb−1 collected with the ... -
Precision Measurement of the Mass and Lifetime of the Ξ0b Baryon
(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 ... -
Prompt Kshort production in pp collisions at sqrt(s)=0.9 TeV
(Physics Letters B, 2010, Vol. 693, No. 2 (Setembre), 2010-09-27)The production of K_short mesons in pp collisions at a centre-of-mass energy of 0.9 TeV is studied with the LHCb detector at the Large Hadron Collider. The luminosity of the analysed sample is determined ... -
Search for CP violation in D+ → K−K+π+ decays
(Physical Review D, 2011, Vol. 84 , No. 11 (Desembre), 2011-12-28)A model-independent search for direct CP violation in the Cabibbo-suppressed decay D+→K−K+π+ in a sample of approximately 370 000 decays is carried out. The data were collected by the LHCb experiment ... -
Search for CP violation in D0 → π− π+ π0 decays with the energy test
(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. ...