12 research outputs found

    Model-independent evidence for J/ψpJ/\psi p contributions to Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays

    Get PDF
    The data sample of Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays acquired with the LHCb detector from 7 and 8~TeV pppp collisions, corresponding to an integrated luminosity of 3 fb1^{-1}, is inspected for the presence of J/ψpJ/\psi p or J/ψKJ/\psi K^- contributions with minimal assumptions about KpK^- p contributions. It is demonstrated at more than 9 standard deviations that Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays cannot be described with KpK^- p contributions alone, and that J/ψpJ/\psi p contributions play a dominant role in this incompatibility. These model-independent results support the previously obtained model-dependent evidence for Pc+J/ψpP_c^+\to J/\psi p charmonium-pentaquark states in the same data sample.Comment: 21 pages, 12 figures (including the supplemental section added at the end

    Quantum numbers of the X(3872)X(3872) state and orbital angular momentum in its ρ0Jψ\rho^0 J\psi decay

    Get PDF
    Angular correlations in B+X(3872)K+B^+\to X(3872) K^+ decays, with X(3872)ρ0J/ψX(3872)\to \rho^0 J/\psi, ρ0π+π\rho^0\to\pi^+\pi^- and J/ψμ+μJ/\psi \to\mu^+\mu^-, are used to measure orbital angular momentum contributions and to determine the JPCJ^{PC} value of the X(3872)X(3872) meson. The data correspond to an integrated luminosity of 3.0 fb1^{-1} of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be JPC=1++J^{PC}=1^{++}. The X(3872)X(3872) is found to decay predominantly through S wave and an upper limit of 4%4\% at 95%95\% C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure

    Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017

    Get PDF
    Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49\ub74% (95% uncertainty interval [UI] 46\ub74–52\ub70). The TFR decreased from 4\ub77 livebirths (4\ub75–4\ub79) to 2\ub74 livebirths (2\ub72–2\ub75), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83\ub78 million people per year since 1985. The global population increased by 197\ub72% (193\ub73–200\ub78) since 1950, from 2\ub76 billion (2\ub75–2\ub76) to 7\ub76 billion (7\ub74–7\ub79) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2\ub70%; this rate then remained nearly constant until 1970 and then decreased to 1\ub71% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2\ub75% in 1963 to 0\ub77% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2\ub77%. The global average age increased from 26\ub76 years in 1950 to 32\ub71 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59\ub79% to 65\ub73%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1\ub70 livebirths (95% UI 0\ub79–1\ub72) in Cyprus to a high of 7\ub71 livebirths (6\ub78–7\ub74) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0\ub708 livebirths (0\ub707–0\ub709) in South Korea to 2\ub74 livebirths (2\ub72–2\ub76) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0\ub73 livebirths (0\ub73–0\ub74) in Puerto Rico to a high of 3\ub71 livebirths (3\ub70–3\ub72) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2\ub70% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation

    An update in the structure, function, and regulation of V-ATPases: the role of the C subunit

    No full text
    Vacuolar ATPases (V-ATPases) are present in specialized proton secretory cells in which they pump protons across the membranes of various intracellular organelles and across the plasma membrane. The proton transport mechanism is electrogenic and establishes an acidic pH and a positive transmembrane potential in these intracellular and extracellular compartments. V-ATPases have been found to be practically identical in terms of the composition of their subunits in all eukaryotic cells. They have two distinct structures: a peripheral catalytic sector (V1) and a hydrophobic membrane sector (V0) responsible for driving protons. V-ATPase activity is regulated by three different mechanisms, which control pump density, association/dissociation of the V1 and V0 domains, and secretory activity. The C subunit is a 40-kDa protein located in the V1 domain of V-ATPase. The protein is encoded by the ATP6V1C gene and is located at position 22 of the long arm of chromosome 8 (8q22.3). The C subunit has very important functions in terms of controlling the regulation of the reversible dissociation of V-ATPases

    African dust impact on aerosol concentrations at twoheights (2250 and 650 masl) in SE Spain

    No full text
    The simultaneous aerosol sampling at two heights in southern Spain may provide valuable information on the vertical structure of the dust transport from North Africa to the Iberian Peninsula. It also allows the characterization of the ambient air at two sites with distinct anthropogenic influence. This work presents the results obtained from the first field campaign of the FRESA project (Impact of dust-laden African air masses and of stratospheric air masses in the Iberian Peninsula. Role of the Atlas Mountains), performed in the period July-November 2017 at El Albergue Universitario in Sierra Nevada (2550 m a.s.l.) and the city of Granada (650 m a.s.l.). The two sites were instrumented with a low-volume sampler with PM10 inlet for daily sampling and mass and chemical composition characterization, a high-volume sampler for total suspended particles (TSP) for weekly sampling and radionuclide activity determination, and with a GRIMM 365 optical particle counter that provides continuously the aerosol size distribution. In Sierra Nevada, daily PM10 concentrations ranged from 0 to 104 \ub5g m-3 depending mainly on the origin and features of the air masses that reach this high-elevation site. Levels overpassed 50 \ub5g m-3 during 5 days and were lower than 20 \ub5g m-3 for 90 days over a total of 124 sampling days. The impact of dust-laden African airflows at this site is particularly intense as dust is transported in most of the cases within welldefined low mid-tropospheric layers. The associated episodic concentrations exceeded 40 \ub5g m-3 . In turn, clean subsiding airflows associated to the polar jet strongly reduced concentrations. In Granada, daily PM10 concentrations are moderately high with values generally between 20 and 40 \ub5g m3 before the first snows fall over Sierra Nevada. Levels were over 50 \ub5g m-3 on 2 days and below 20 \ub5g m-3 on 32 days over a total of 103 sampling days. The highest concentrations do not reach the peaks found at Sierra Nevada. The impact of anthropogenic aerosols of local origin, which are accumulated during highstability conditions, and also of regional origin (both from the Mediterranean and from the SW Iberian Peninsula) is significant. The contribution of African dust outbreaks superimposes to background ambient air concentrations and in some events the increase is observed one day after the African dust impacts over Sierra Nevada. After the first snowfall of the year in Sierra Nevada, there\u2019s a change in wind regime, PM10 levels drop and only accumulation periods or African dust events are able to increase concentrations at levels similar to those detected before. The diurnal pattern of PM10 and particle number concentrations (both of the fine and the coarse fractions) at Granada presents the two typical peaks in the morning and evening; there\u2019s one peak at 16 Local Time - LT in Sierra Nevada. Particle concentrations are smaller in the colder period than in the warmer one, primarily due to the much higher concentrations in the coarse fraction (> 1 \ub5m) in summertime. However, the fine fraction (submicronic) presents a stronger morning peak (centered about 10 LT) in the colder period and also concentrations are slightly higher at about 20-21 LT. Trajectories (calculated 96-hour backward in time starting at 00, 06, 12 and 18 UTC with HYSPLIT using ERAInterim data of 0.5 degree resolution) show that air flows are quite often decoupled at the two altitudes. Dust-laden African flows reached Sierra Nevada on 33 days; of these, dust was advected poleward over the Atlas near the Algerian-Moroccan border on 19 days and on the remaining 14 it followed a pathway over the Atlantic close to the Moroccan coast. However, only on 3 days large-scale flows of African origin reached Granada. In turn, airflows reaching Granada passed previously over the western Mediterranean Sea on 32 days while only on 3 days Mediterranean flows reached Sierra Nevada. Moreover, the total residence time over North Africa of the air parcels reaching Sierra Nevada amounts 9474 hours, and during the corresponding days the total residence time over the Mediterranean of the parcels reaching Granada is 10,055 hours. In contrast, the residence time of the air masses arriving to Granada after residing over Africa is only of 56 hours. This implies that during African dust outbreaks the air masses reaching the study area at the lowest levels do not have African origin but have resided over the Mediterranean, and it is in accordance with Cabello et al. (2017) for M\ue1laga and Orza et al. (submitted) for the whole Spanish Mediterranean. Chemical analysis of the PM10 samples (in progress) will provide the first direct experimental evidence of this fact. The identification of episodes was done by analysing the fine and coarse fractions registered with the Grimm OPCs at the two sites and by the aerosol optical depth (AOD) and Angstr\uf6m exponent (AE) from the AERONET station of IISTA-CEAMA in Granada, in combination with back-trajectories. The low availability of satellite information (Dust RGB product and MODIS aerosol properties) is a major limitation at the study area. A number of distinct episodes can be identified: strong African dust impact at Sierra Nevada while Granada is heavily polluted by anthropogenic aerosols (1 August 2017); strong African dust impact at Sierra Nevada which is observed the following day in Granada (15-16 August 2017); African dust outbreaks impacting simultaneously both sites (e.g., 25 November 2017); episode of accumulation of pollutants at Granada whilst very low concentrations are registered at Sierra Nevada (19-24 November 2017); impact of remote fires at both sites (27 July and 9 September 2017) and fair air quality at both sites (e.g., 16 September 2017). Differences in the onset and duration of the African dust episodes are found between the two sites as well as between the surface and the columnar measurements

    The K2-OjOS Project*New and revisited planets and candidates in K2 campaigns 5, 16, & 18

    No full text
    We present the first results of K2-OjOS, a collaborative project between professional and amateur astronomers primarily aimed to detect, characterize, and validate new extrasolar planets. For this work, 10 amateur astronomers looked for planetary signals by visually inspecting the 20 427 light curves of K2 campaign 18 (C18). They found 42 planet candidates, of which 18 are new detections and 24 had been detected in the overlapping C5 by previous works. We used archival photometric and spectroscopic observations, as well as new high-spatial resolution images in order to carry out a complete analysis of the candidates found, including a homogeneous characterization of the host stars, transit modelling, search for transit timing variations and statistical validation. As a result, we report four new planets (K2-355 b, K2-356 b, K2-357 b, and K2-358 b) and 14 planet candidates. Besides, we refine the transit ephemeris of the previously published planets and candidates by modelling C5, C16 (when available) and C18 photometric data jointly, largely improving the period and mid-transit time precision. Regarding individual systems, we highlight the new planet K2-356 b and candidate EPIC 211537087.02 being near a 2:1 period commensurability, the detection of significant TTVs in the bright star K2-184 (V = 10.35), the location of K2-103 b inside the habitable zone according to optimistic models, the detection of a new single transit in the known system K2-274, and the disposition reassignment of K2-120 b, which we consider as a planet candidate as the origin of the signal cannot be ascertained

    Measurement of CP violation and constraints on the CKM angle γ in B± → DK± with D → K0Sπ+π− decays

    Get PDF
    A model-dependent amplitude analysis of B± → DK± with D → K0 Sπ+π− decays is performed using proton–proton collision data, corresponding to an integrated luminosity of 1 fb−1, recorded by LHCb at a centre-of-mass energy of 7 TeV in 2011. Values of the CP violation observables x± and y±, which are sensitive to the CKM angle γ, are measured to be x− = +0.027 ± 0.044+0.010 −0.008 ± 0.001, y− = +0.013 ± 0.048+0.009 −0.007 ± 0.003, x+ = −0.084 ± 0.045 ± 0.009 ± 0.005, y+ = −0.032 ± 0.048+0.010 −0.009 ± 0.008, where the first uncertainty is statistical, the second systematic and the third arises from the uncertainty of the D → K0 Sπ+π− amplitude model. The value of γ is determined to be (84+49 −42)◦, including all sources of uncertainty. Neutral D meson mixing is found to have negligible effect

    Measurement of the forward W boson cross-section in pp collisions at s = 7 s=7 \sqrt{s}=7 TeV

    No full text

    Study of \upchi _{{\mathrm {b}}} \u3c7 b meson production in p\mathrm {p} p p\mathrm {p} p collisions at s=7\sqrt{s}=7 s = 7 and 8TeV8{\mathrm {\,TeV}} 8 TeV and observation of the decay \upchi _{{\mathrm {b}}}\mathrm {(3P)} \rightarrow \Upsilon \mathrm {(3S)} {\upgamma } \u3c7 b ( 3 P ) \u2192 \u3a5 ( 3 S ) \u3b3

    No full text
    corecore