82 research outputs found

    Radiative BBγB^{*}\to B\gamma and DDγD^{*}\to D\gamma decays in light cone QCD sum rules

    Full text link
    The radiative decays B(D)B(D)γ B^{*} (D^{*})\rightarrow B(D) \gamma are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson decays are in good agreement with the existing experimental data.Comment: 13 pages, Latex, 3 figure

    Vibration-induced "thermally activated" jamming transition in granular media

    Full text link
    The quasi-static frequency response of a granular medium is measured by a forced torsion oscillator method, with forcing frequency fpf_{p} in the range 10410^{-4} Hz to 5 Hz, while weak vibrations at high-frequency fsf_{s}, in the range 50 Hz to 200 Hz, are generated by an external shaker. The intensity of vibration, Γ\Gamma , is below the fluidization limit. A loss factor peak is observed in the oscillator response as a function of Γ\Gamma or fpf_{p}. In a plot of lnfp\ln f_{p} against 1/Γ1/\Gamma , the position of the peak follows an Arrhenius-like behaviour over four orders of magnitude in fpf_{p}. The data can be described as a stochastic hopping process involving a probability factor exp(Γj/Γ)\exp(-\Gamma_{j}/\Gamma) with Γj\Gamma_{j} a fsf_{s}-dependent characteristic vibration intensity. A fsf_{s}-independent description is given by exp(τj/τ)\exp(-\tau_{j}/\tau), with τj\tau_{j} an intrinsic characteristic time, and τ=Γn/2πfs\tau =\Gamma ^{n}/2\pi f_{s}, n=0.5-0.6, an empirical control parameter with unit of time. τ\tau is seen as the effective average time during which the perturbed grains can undergo structural rearrangement. The loss factor peak appears as a crossover in the dynamic behaviour of the vibrated granular system, which, at the time-scale 1/fp 1/f_{p}, is solid-like at low Γ\Gamma, and the oscillator is jammed into the granular material, and is fluid-like at high Γ\Gamma, where the oscillator can slide viscously.Comment: Final version to appear in PR

    Study of the Process e+eKL0KS0e^+e^- \to K^0_L K^0_S in the C.M.Energy Range 1.05-1.38 GeV with CMD-2

    Full text link
    The process e+eKL0KS0e^+e^- \to K^0_L K^0_S has been studied with the CMD-2 detector using about 950 events detected in the center-of-mass energy range from 1.05 to 1.38 GeV. The cross section exceeds the expectation based on the contributions of the rho(770), omega(782) and phi(1020) mesons only.Comment: 12 pages, 3 figures, uses elsart.cls, submitted to Physics Letters

    Study of the Process e+ e- --> omega pi0 --> pi0 pi0 gamma in c.m. Energy Range 920--1380 MeV at CMD-2

    Full text link
    The cross section of the process e+ e- --> omega pi0 --> pi0 pi0 gamma has been measured in the c.m. energy range 920-1380 MeV with the CMD-2 detector. Its energy dependence is well described by the interference of the rho(770) and rho'(1450) mesons decaying to omega pi0. Upper limits for the cross sections of the direct processes e+ e- --> pi0 pi0 gamma, eta pi0 gamma have been set.Comment: Accepted for publication in PL

    Associated Production of a KK-Graviton with a Higgs Boson via Gluon Fusion at the LHC

    Full text link
    In order to solve the hierarchy problem, several extra-dimensional models have received considerable attention. We have considered a process where a Higgs boson is produced in association with a KK-graviton (GKKG_{\rm KK}) at the LHC. At the leading order, this process occurs through gluon fusion mechanism gghGKKgg \to h G_{\rm KK} via a quark loop. We compute the cross section and examine some features of this process in the ADD model. We find that the quark in the loop does not decouple in the large quark-mass limit just as in the case of gghgg\to h process. We compute the cross section of this process for the case of the RS model also. We examine the feasibility of this process being observed at the LHC.Comment: 18 pages, 11 figures. Calculation in the Higgs effective theory framework adde

    An embedding technique to determine ττ backgrounds in proton-proton collision data

    Get PDF

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

    Get PDF
    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Search for light pseudoscalar boson pairs produced from decays of the 125 GeV Higgs boson in final states with two muons and two nearby tracks in pp collisions at √s = 13 TeV

    Get PDF

    Measurement of the azimuthal anisotropy of Y(1S) and Y(2S) mesons in PbPb collisions at √S^{S}NN = 5.02 TeV

    Get PDF
    The second-order Fourier coefficients (υ2_{2}) characterizing the azimuthal distributions of Υ(1S) and Υ(2S) mesons produced in PbPb collisions at sNN\sqrt{s_{NN}} = 5.02 TeV are studied. The Υmesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7 nb1^{-1}. The scalar product method is used to extract the υ2_{2} coefficients of the azimuthal distributions. Results are reported for the rapidity range |y| < 2.4, in the transverse momentum interval 0 < pT_{T} < 50 GeV/c, and in three centrality ranges of 10–30%, 30–50% and 50–90%. In contrast to the J/ψ mesons, the measured υ2_{2} values for the Υ mesons are found to be consistent with zero
    corecore