LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2019). Measurement of the branching fractions of the decays D+ -> K-K+K+, D+ -> pi-pi(+) K+ and D-s(+) -> pi-K+K+. J. High Energy Phys., 03(3), 176–24pp.
Abstract: The branching fractions of the doubly Cabibbo-suppressed decays D+ ! K, D+ ! and D+ s ! are measured using the decays D+ ! K and D+ s ! K as normalisation channels. The measurements are performed using proton-proton collision data collected with the LHCb detector at a centre-of-mass energy of 8TeV, corresponding to an integrated luminosity of 2.0 fb. The results are B (D+ ! K) B (D+ ! K) = (6 : 541 0 : 025 0 : 042) 10 B (D+ ! ) B (D+ ! K) = (5 : 231 0 : 009 0 : 023) 10 B (D+ s ! ) B (D+ s ! K) = (2 : 372 0 : 024 0 : 025) 10 where the uncertainties are statistical and systematic, respectively. These are the most precise measurements up to date.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2019). Measurement of the ratio of branching fractions of the decays0(2S) and arrange Lambda. J. High Energy Phys., 03(3), 126–16pp.
Abstract: Using pp collisions corresponding to 3 fb integrated luminosity, recorded by the LHCb experiment at centre- of- mass energies of 7 and 8 TeV, the ratio of branching fractions B (0b ! (2 S) ) =B (0b ! J= ) = 0 : 513 0 : 023 (stat) 0 : 016 (syst) 0 : 011 (B) is determined. The first uncertainty is statistical, the second is systematic and the third is due to the external branching fractions used.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2019). Measurement of the relative B- -> D-0 / D*(0) / D**(0)mu(-)(nu)over-bar(mu) branching fractions using B- mesons from (B)over-bar(S)(2)*(0) decays. Phys. Rev. D, 99(9), 092009–16pp.
Abstract: The decay of the narrow resonance (B) over bar (s2)*(0 )-> B(-)K(+)can be used to determine the B- momentum in partially reconstructed decays without any assumptions on the decay products of the r meson. This technique is employed for the first time to distinguish contributions from D-0, D*(0), and higher-mass charmed states (D(0)) in semileptonic B- decays by using the missing-mass distribution. The measurement is performed using a data sample corresponding to an integrated luminosity of 3.0 fb(-1) collected with the LHCb detector in pp collisions at center-of-mass energies of 7 and 8 TeV. The resulting branching fractions relative to the inclusive B- -> (DX)-X-0 mu(-)(nu) over bar (mu )are f(D)(0)= B(B- -> D-0 mu(-)(nu) over bar mu/B(B- ->(DX)-D- -X-0 mu(-)(nu) over bar (mu))( )= 0.25( )+/- 0.06, f( D)(0 )= B(B- -> (D(0) -> (DX)-X-0)mu(-)(nu) over bar (mu))/B(B--> (DX)-X-0 mu(-)(nu) over bar (mu)) = 0.21 +/- 0.07, with f(D)*(0) = 1 – f(D)(0) – f(D)(0) making up the remainder.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., et al. (2020). Precision measurement of the Xi(++)(cc) mass. J. High Energy Phys., 02(2), 049–18pp.
Abstract: A measurement of the Xi cc++ candidates are reconstructed via the decay modes Xi cc++->?c+K-pi+pi+ and Xi cc++->Xi c+pi+. The result, 3621.55 +/- 0.23 (stat) +/- 0.30 (syst) MeV/c(2), is the most precise measurement of the Xi cc++ mass to date.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., et al. (2019). Search for Lepton-Universality Violation in B+ -> K(+)l(+)l(-) Decays. Phys. Rev. Lett., 122(19), 191801–13pp.
Abstract: A measurement of the ratio of branching fractions of the decays B+ -> K+mu(+)mu(-) and B+ -> K(+)e(+)e(-) is presented. The proton-proton collision data used correspond to an integrated luminosity of 5.0 fb(-1) recorded with the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. For the dilepton mass-squared range 1.1 < q(2) < 6.0 GeV2/c(4) the ratio of branching fractions is measured to be R-K = 0.846(-0.054-0.014)(+0.060+0.016), where the first uncertainty is statistical and the second systematic. This is the most precise measurement of R-K to date and is compatible with the standard model at the level of 2.5 standard deviations.
|
