Browsing La Salle by Subject "Col·lisions (Física nuclear)"
Now showing items 21-40 of 219
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Differential branching fraction and angular analysis of Λ 0 b → Λμ+μ− decays
(Journal of High Energy Physics, 2015, Vol. 2015, No.115 (Juny), 2015-06-17)The differential branching fraction of the rare decay Λ 0 b → Λμ+μ− is measured as a function of q2, the square of the dimuon invariant mass. The analysis is performed using proton-proton collision ... -
Differential branching fractions and isospin asymmetries of B → K (*) μ + μ − decays
(Journal of High Energy Physics, 2014, Vol. 2014, No.6 (Juny), 2014-06-26)The isospin asymmetries of B → Kμ + μ − and B → K * μ + μ − decays and the partial branching fractions of the B 0 → K 0 μ + μ −, B + → K + μ + μ − and B + → K *+ μ + μ − decays are measured as functions ... -
Effective lifetime measurements in the B0s → K+K− , B0 → K+π− and B0s → π+K− decays
(Physics Letters B , 2014, Vol. 736 (Setembre), 2014-09-07)Measurements of the effective lifetimes in the B0s→K+K−, B0→K+π− and B0s→π+K− decays are presented using 1.0 fb−1 of pp collision data collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. ... -
Evidence for CP Violation in B+→p¯pK+ Decays
(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 ... -
Evidence for the decay B+c→J/ψ3π+2π−
(Journal of High Energy Physics, 2014, Vol. 2014, No.2 (Febrer), 2014-05-30)Evidence is presented for the decay B+c→J/ψ3π+2π− using proton-proton collision data, corresponding to an integrated luminosity of 3 fb−1, collected with the LHCb detector. A signal yield of 32 ± 8 ... -
Evidence for the decay B0 → J/ψω and measurementof the relative branching fractions of B0s meson decays to J/ψη and J/ψη′
(Nuclear Physics B, 2012, Vol. 867, No. 3, 2012-10)First evidence of the B0→J/ψω decay is found and the B0s→J/ψη and B0s→J/ψη′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experimentin ... -
Evidence for the decay X(3872) →ψ(2S)γ
(Nuclear Physics B, 2014, Vol. 886, 2014-09)Evidence for the decay mode X(3872) →ψ(2S)γ in B+→X(3872)K+decays is found with a sig-nificance of 4.4 standard deviations. The analysis is based on a data sample of proton–proton collisions, corresponding ... -
Evidence for the Strangeness-Changing Weak Decay Ξ−b→Λ0bπ−
(Physical Review Letters, 2015, Vol. 115, No. 24 (Desembre), 2015-12-11)Using a pp collision data sample corresponding to an integrated luminosity of 3.0 fb−1, collected by the LHCb detector, we present the first search for the strangeness-changing weak decay Ξ−b→Λ0bπ−. ... -
Exclusive J/ψ and ψ(2S) production in pp collisions at √s= 7 TeV
(Journal of Physics G-Nuclear and Particle Physics, 2013, Vol. 40, No. 4, 2013-02)Exclusive J/ψ and ψ(2S) vector meson production has been observed in the dimuon channel using the LHCb detector. The cross-section times branching fractions to two muons with pseudorapidities between ... -
First Evidence for the Decay B0s→μ+μ−
(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 ... -
First Measurement of the Charge Asymmetry in Beauty-Quark Pair Production
(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 ... -
First measurement of time-dependent CP violation in B0s→K+K− decays
(Journal of High Energy Physics, 2013, Vol. 2013, No.10 (Octubre), 2013-10-25)Direct and mixing-induced CP-violating asymmetries in B0s→K+K− decays are measured for the first time using a data sample of pp collisions, corresponding to an integrated luminosity of 1.0 fb−1, collected ... -
First observation and amplitude analysis of the B−→D+K−π− decay
(Physical Review D, 2015, Vol.91, No.9 (Maig), 2015-05-05)The B−→D+K−π− decay is observed in a data sample corresponding to 3.0 fb−1 of pp collision data recorded by the LHCb experiment during 2011 and 2012. Its branching fraction is measured to be ... -
First observation and measurement of the branching fraction for the decay B 0 s → D ∗ s ∓ K ±
(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 ... -
First observation of B0 → D∗+ Xμ−ν decays
(Physics Letters B, Vol. 698, No. 1 (Març 2011), 2011)Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and Bs -> D0 K+ X mu nu are detected. Two structures ... -
First observation of B0s → J/ψ f0(980) decays
(Physics Letters B, Vol. 698, No 2 (Abril 2011), 2011-01)Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the hadronic decayB0s→J/ψf0(980) is observed. ThisCP eigenstate mode could be used to measure ... -
First observation of the decay B+c → J/ψ K+
(Journal of High Energy Physics, 2013, Vol. 2013, No.9 (Setembre), 2013-09-13)The decay B+c→J/ψK+ is observed for the first time using a data sample, corresponding to an integrated luminosity of 1.0 fb−1, collected by the LHCb experiment in pp collisions at a centre-of-mass energy ... -
First observation of the decay B+→π+μ+μ−
(Journal of High Energy Physics, 2012, Vol. 2012, No.12 (Desembre), 2012-12-21)A discovery of the rare decay B + → π + μ + μ − is presented. This decay is observed for the first time, with 5.2 σ significance. The observation is made using pp collision data, corresponding to an ... -
First observation of the decay B0s→K∗0K∗0
(Physics Letters B, 2012,Vol. 709, No. 1-2 (Març 2012), 2012-03-13)The first observation of the decay $\kstarkstar$ is reported using 35\invpb of data collected by LHCb in proton-proton collisions at a centre-of-mass energy of 7 TeV. A total of $49.8 \pm 7.5$ $B^0_s ... -
First Observation of Top Quark Production in the Forward Region
(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 ...