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A bstract We propose an approach for measuring the moments of the hadronic invariant mass distribution in semileptonic B s 0 meson decays using a sum-of-exclusive technique. Using the present and foreseen knowledge about exclusive semileptonic B s 0 decays, we estimate the uncertainties on moments of the kinematic distribution. Semileptonic B s 0 decays can be described, as their B 0 counterpart, using the Heavy Quark Expansion (HQE), with the only difference between the B s 0 and B 0 mesons being the SU(3) F breaking effects that change the numerical values of the non-perturbative HQE parameters. We extract the HQE parameters for the B s 0 decays from our estimates of the moments, showing the potential of the proposed method. We identify a set of required measurements for a future precision measurement.

We propose an approach for measuring the moments of the hadronic invariant mass distribution in semileptonic$$ {B}_s^0 $$B s 0 meson decays using a sum-of-exclusive technique. Using the present and foreseen knowledge about exclusive semileptonic$$ {B}_s^0 $$B s 0 decays, we estimate the uncertainties on moments of the kinematic distribution. Semileptonic$$ {B}_s^0 $$B s 0 decays can be described, as their B 0 counterpart, using the Heavy Quark Expansion (HQE), with the only difference between the$$ {B}_s^0 $$B s 0 and B 0 mesons being the SU(3) F breaking effects that change the numerical values of the non-perturbative HQE parameters. We extract the HQE parameters for the$$ {B}_s^0 $$B s 0 decays from our estimates of the moments, showing the potential of the proposed method. We identify a set of required measurements for a future precision measurement.

The hydrothermal-vent tubeworm Riftia pachyptila relies entirely on its intracellular chemoautotrophic symbionts to sustain its metabolism. The host must therefore provide them with inorganic metabolites, including carbon. This study describes a tool for studying cell processes occurring in a bacteria-containing cell by the dissociation of trophosome cell types. The physiological assays performed on cell preparations focused on carbon dioxide conversion and transport processes. Trophosome tissue was mechanically dissociated, resulting in cell suspensions enriched in small (7-20 mu m) bacteriocytes, which were viable for several hours. In addition, medium-term cell cultures were also attempted. As a start to the understanding of the CO2 metabolism of these cells, we were interested in evidence of carbonic anhydrase (CA) isoforms, ATPases and chloride exchangers. Variations in intracellular and extracellular pH, and in intracellular concentrations of sodium, potassium and chloride, were followed after addition of selective inhibitors. The data presented here suggest the occurrence of potential cytosolic and membrane-associated carbonic anhydrase isoforms in the bacteriocytes, proton-driven sodium-ATPases and a well represented anion transporter exchanging intracellular chloride against extracellular anions. [PUBLICATION ABSTRACT]

In the Standard Model of particle physics, the strength of the couplings of the b quark to the u and c quarks, | V ub | and | V cb |, are governed by the coupling of the quarks to the Higgs boson. Using data from the LHCb experiment at the Large Hadron Collider, the probability for the Λ b 0 baryon to decay into the p final state relative to the final state is measured. Combined with theoretical calculations of the strong interaction and a previously measured value of | V cb |, the first | V ub | measurement to use a baryonic decay is performed. This measurement is consistent with previous determinations of | V ub | using B meson decays to specific final states and confirms the existing incompatibility with those using an inclusive sample of final states. The accurate determination of quark mixing parameters is essential for the understanding of the Standard Model. The LHCb collaboration now reports the coupling strength of the b quark to the u quark through the measurement of a baryonic decay mode.

A bstract The production cross-section of J/ψ pairs is measured using a data sample of pp collisions collected by the LHCb experiment at a centre-of-mass energy of s = 13 TeV, corresponding to an integrated luminosity of 279 ±11 pb −1 . The measurement is performed for J/ψ mesons with a transverse momentum of less than 10 GeV/ c in the rapidity range 2 . 0 < y < 4 . 5. The production cross-section is measured to be 15 . 2 ± 1 . 0 ± 0 . 9 nb. The first uncertainty is statistical, and the second is systematic. The differential cross-sections as functions of several kinematic variables of the J/ψ pair are measured and compared to theoretical predictions.

We propose an approach for measuring the moments of the hadronic invariant mass distribution in semileptonic Bs0 meson decays using a sum-of-exclusive technique. Using the present and foreseen knowledge about exclusive semileptonic Bs0 decays, we estimate the uncertainties on moments of the kinematic distribution. Semileptonic Bs0 decays can be described, as their B0 counterpart, using the Heavy Quark Expansion (HQE), with the only difference between the Bs0 and B0 mesons being the SU(3)F breaking effects that change the numerical values of the non-perturbative HQE parameters. We extract the HQE parameters for the Bs0 decays from our estimates of the moments, showing the potential of the proposed method. We identify a set of required measurements for a future precision measurement.

Abstract We propose an approach for measuring the moments of the hadronic invariant mass distribution in semileptonic B s 0 $$ {B}_s^0 $$ meson decays using a sum-of-exclusive technique. Using the present and foreseen knowledge about exclusive semileptonic B s 0 $$ {B}_s^0 $$ decays, we estimate the uncertainties on moments of the kinematic distribution. Semileptonic B s 0 $$ {B}_s^0 $$ decays can be described, as their B 0 counterpart, using the Heavy Quark Expansion (HQE), with the only difference between the B s 0 $$ {B}_s^0 $$ and B 0 mesons being the SU(3) F breaking effects that change the numerical values of the non-perturbative HQE parameters. We extract the HQE parameters for the B s 0 $$ {B}_s^0 $$ decays from our estimates of the moments, showing the potential of the proposed method. We identify a set of required measurements for a future precision measurement.

The production of the η c ( 1 S ) state in proton-proton collisions is probed via its decay to the p p ¯ final state with the LHCb detector, in the rapidity range 2.0 < y < 4.5 and in the meson transverse-momentum range p T > 6.5 GeV / c . The cross-section for prompt production of η c ( 1 S ) mesons relative to the prompt J / ψ cross-section is measured, for the first time, to be σ η c ( 1 S ) / σ J / ψ = 1.74 ± 0.29 ± 0.28 ± 0 . 18 B at a centre-of-mass energy s = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb - 1 , and σ η c ( 1 S ) / σ J / ψ = 1.60 ± 0.29 ± 0.25 ± 0 . 17 B at s = 8 TeV using 2.0 fb - 1 . The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the η c ( 1 S ) and J / ψ decays to the p p ¯ final state. In addition, the inclusive branching fraction of b -hadron decays into η c ( 1 S ) mesons is measured, for the first time, to be B ( b → η c X ) = ( 4.88 ± 0.64 ± 0.29 ± 0 . 67 B ) × 10 - 3 , where the third uncertainty includes also the uncertainty on the J / ψ inclusive branching fraction from b -hadron decays. The difference between the J / ψ and η c ( 1 S ) meson masses is determined to be 114.7 ± 1.5 ± 0.1 MeV / c 2 .

Measurements are presented of electroweak boson production using data from pp collisions at a centre-of-mass energy of s√=8TeV. The analysis is based on an integrated luminosity of 2.0fb−1 recorded with the LHCb detector. The bosons are identified in the W→μν and Z→μ+μ− decay channels. The cross-sections are measured for muons in the pseudorapidity range 2.0<η<4.5, with transverse momenta pT>20GeV/c and, in the case of the Z boson, a dimuon mass within 60

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