The first observation of the Bs0 → D∗+D∗- decay and the measurement of its branching ratio relative to the B0 → D∗+D∗- decay are presented. The data sample used corresponds to an integrated luminosity of 9 fb-1 of p...
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The ratio of branching fractions of Bc+ → Bs0π+ and Bc+ → J/ψπ+ decays is measured with proton-proton collision data of a centre-of-mass energy of 13 TeV. The data were collected with the LHCb experiment during 2...
Background: The COVID-19 pandemic highlighted gaps in health surveillance systems, disease prevention, and treatment globally. Among the many factors that might have led to these gaps is the issue of the financing of ...
Background: The COVID-19 pandemic highlighted gaps in health surveillance systems, disease prevention, and treatment globally. Among the many factors that might have led to these gaps is the issue of the financing of national health systems, especially in low-income and middle-income countries (LMICs), as well as a robust global system for pandemic preparedness. We aimed to provide a comparative assessment of global health spending at the onset of the pandemic;characterise the amount of development assistance for pandemic preparedness and response disbursed in the first 2 years of the COVID-19 pandemic;and examine expectations for future health spending and put into context the expected need for investment in pandemic preparedness. Methods: In this analysis of global health spending between 1990 and 2021, and prediction from 2021 to 2026, we estimated four sources of health spending: development assistance for health (DAH), government spending, out-of-pocket spending, and prepaid private spending across 204 countries and territories. We used the Organisation for Economic Co-operation and Development (OECD)'s Creditor Reporting System (CRS) and the WHO Global Health Expenditure database (GHED) to estimate spending. We estimated development assistance for general health, COVID-19 response, and pandemic preparedness and response using a keyword search. Health spending estimates were combined with estimates of resources needed for pandemic prevention and preparedness to analyse future health spending patterns, relative to need. Findings: In 2019, at the onset of the COVID-19 pandemic, US$9·2 trillion (95% uncertainty interval [UI] 9·1–9·3) was spent on health worldwide. We found great disparities in the amount of resources devoted to health, with high-income countries spending $7·3 trillion (95% UI 7·2–7·4) in 2019;293·7 times the $24·8 billion (95% UI 24·3–25·3) spent by low-income countries in 2019. That same year, $43·1 billion in development assistance was provided
The production of χc1(3872) and ψ(2S) hadrons is studied as a function of charged particle multiplicity in pp collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 2 fb−1. For...
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The production of χc1(3872) and ψ(2S) hadrons is studied as a function of charged particle multiplicity in pp collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 2 fb−1. For both states, the fraction that is produced promptly at the collision vertex is found to decrease as charged particle multiplicity increases. The ratio of χc1(3872) to ψ(2S) cross sections for promptly produced particles is also found to decrease with multiplicity, while no significant dependence on multiplicity is observed for the equivalent ratio of particles produced away from the collision vertex in b-hadron decays. This behavior is consistent with a calculation that models the χc1(3872) structure as a compact tetraquark. Comparisons with model calculations and implications for the binding energy of the χc1(3872) state are discussed.
The first observations of B0→D¯*(2007)0K+π− and Bs0→D¯*(2007)0K−π+ decays are presented, and their branching fractions relative to that of the B0→D¯*(2007)0π+π− decay are reported. These modes ca...
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The first observations of B0→D¯*(2007)0K+π− and Bs0→D¯*(2007)0K−π+ decays are presented, and their branching fractions relative to that of the B0→D¯*(2007)0π+π− decay are reported. These modes can potentially be used to investigate the spectroscopy of charm and charm-strange resonances and to determine the angle γ of the Cabibbo-Kobayashi-Maskawa unitarity triangle. It is also important to understand them as a source of potential background in determinations of γ from B+→DK+ and B0→DK+π− decays. The analysis is based on a sample corresponding to an integrated luminosity of 5.4 fb−1 of proton-proton collision data at 13 TeV center-of-mass energy recorded with the LHCb detector. The D¯*(2007)0 mesons are fully reconstructed in the D¯0π0 and D¯0γ channels with the D¯0→K+π− decay. A novel weighting method is used to subtract background while simultaneously applying an event-by-event efficiency correction to account for resonant structures in the decays.
A measurement of the ratios of the effective decay widths of D0→π−π+ and D0→K−K+ decays over that of D0→K−π+ decays is performed with the LHCb experiment using proton–proton collisions at a centre-of-mass energ...
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A measurement of the ratios of the effective decay widths of D0→π−π+ and D0→K−K+ decays over that of D0→K−π+ decays is performed with the LHCb experiment using proton–proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb−1. These observables give access to the charm mixing parameters yCPππ−yCPKπ and yCPKK−yCPKπ, and are measured as yCPππ−yCPKπ=(6.57±0.53±0.16)×10−3, yCPKK−yCPKπ=(7.08±0.30±0.14)×10−3, where the first uncertainties are statistical and the second systematic. The combination of the two measurements is yCP−yCPKπ=(6.96±0.26±0.13)×10−3, which is four times more precise than the previous world average.
An improved measurement of the decay Bs0→μ+μ− and searches for the decays B0→μ+μ− and Bs0→μ+μ−γ are performed at the LHCb experiment using data collected in proton-proton collisions at s=7, 8 and 13 TeV, cor...
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An improved measurement of the decay Bs0→μ+μ− and searches for the decays B0→μ+μ− and Bs0→μ+μ−γ are performed at the LHCb experiment using data collected in proton-proton collisions at s=7, 8 and 13 TeV, corresponding to integrated luminosities of 1, 2 and 6 fb−1, respectively. The Bs0→μ+μ− branching fraction and effective lifetime are measured to be B(Bs0→μ+μ−)=(3.09−0.43−0.11+0.46+0.15)×10−9 and τ(Bs0→μ+μ−)=(2.07±0.29±0.03) ps, respectively, where the uncertainties include both statistical and systematic contributions. No significant signal for B0→μ+μ− and Bs0→μ+μ−γ decays is found and the upper limits B(B0→μ+μ−)<2.6×10−10 and B(Bs0→μ+μ−γ)<2.0×10−9 at 95% confidence level are determined, where the latter is limited to the range mμμ>4.9 GeV/c2. Additionally, the ratio between the B0→μ+μ− and Bs0→μ+μ− branching fractions is measured to be Rμ+μ−<0.095 at 95% confidence level. The results are in agreement with the Standard Model predictions.
Submillimeter/millimeter observations of dusty star-forming galaxies with the Atacama Large Millimeter/submillimeter Array (ALMA) have shown that dust continuum emission generally occurs in compact regions smaller tha...
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First evidence of a structure in the J/ψΛinvariant mass distribution is obtained from an amplitude analysis of■b^(-)J/ψΛK^(-)*** observed structure is consistent with being due to a charmonium pentaquark with str...
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First evidence of a structure in the J/ψΛinvariant mass distribution is obtained from an amplitude analysis of■b^(-)J/ψΛK^(-)*** observed structure is consistent with being due to a charmonium pentaquark with strangeness with a significance of 3.1r including systematic uncertainties and lookelsewhere *** mass and width are determined to be 4458:8±2:9t4:7-1:1 MeV and 17:3±6:5t8:0-5:7 MeV,respectively,where the quoted uncertainties are statistical and *** structure is also consistent with being due to two *** addition,the narrow excited■^(-)states,N■(1690)and■(1820),are seen for the first time in a■b^(-)decay,and their masses and widths are measured with improved *** analysis is performed using pp collision data corresponding to a total integrated luminosity of 9 fb^(-1),collected with the LHCb experiment at centre-of-mass energies of 7,8 and 13 TeV.
A simultaneous analysis of the B+ → K++− and B0 → K∗0+− decays is performed to test muon-electron universality in two ranges of the square of the dilepton invariant mass, q2. The measurement uses a sample of beauty ...
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