Debastiani, V. R., Dias, J. M., & Oset, E. (2017). Study of the DKK and DK(K)over-bar systems. Phys. Rev. D, 96(1), 016014–9pp.
Abstract: Using the fixed center approximation to Faddeev equations, we investigate the DKK and DK (K) over bar three-body systems, considering that the DK dynamically generates, through its I = 0 component, the D(so)(*()2317) molecule. According to our findings, for the DK (K) over bar interaction we find evidence of a state I(J(p)) = 1/2 (0(-)) just above the D-s0(*)(2317) (K) over bar threshold and around the Df(0)(980) threshold, with mass of about 2833-2858 MeV, made mostly of Df(0)(980). On the other hand, no evidence related to a state from the DKK interaction is found. The state found could be seen in the ppD invariant mass.
|
LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2017). Observation of the B+ -> D*K-(+) pi(+) decay. Phys. Rev. D, 96(1), 011101–10pp.
Abstract: The B+ -> D*K--(+)pi(+) decay potentially provides an excellent way to investigate charm meson spectroscopy. The decay is searched for in a sample of proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). A clear signal is observed, and the ratio of its branching fraction to that of the B+ -> D*(-)pi(+)pi(+) normalization channel is measured to be beta(B+ -> D*K--(+)pi(+))/beta(B+ -> D*(-)pi(+)pi(+)) = (6.39 +/- 0.27 +/- 0.48) x 10(-2); where the first uncertainty is statistical and the second is systematic. This is the first observation of the B+ -> D*K--(+)pi(+) decay.
|
ANTARES, I. C., LIGO and Virgo Collaborations(Albert, A. et al), Barrios-Marti, J., Hernandez-Rey, J. J., Illuminati, G., Lotze, M., Sanchez-Losa, A., et al. (2017). Search for high-energy neutrinos from gravitational wave event GW151226 and candidate LVT151012 with ANTARES and IceCube. Phys. Rev. D, 96(2), 022005–15pp.
Abstract: The Advanced LIGO observatories detected gravitational waves from two binary black hole mergers during their first observation run (O1). We present a high-energy neutrino follow-up search for the second gravitational wave event, GW151226, as well as for gravitational wave candidate LVT151012. We find two and four neutrino candidates detected by IceCube, and one and zero detected by ANTARES, within +/- 500 s around the respective gravitational wave signals, consistent with the expected background rate. None of these neutrino candidates are found to be directionally coincident with GW151226 or LVT151012. We use nondetection to constrain isotropic-equivalent high-energy neutrino emission from GW151226, adopting the GW event's 3D localization, to less than 2 x 10(51)-2 x 10(54) erg.
|
Rocco, N., Alvarez-Ruso, L., Lovato, A., & Nieves, J. (2017). Electromagnetic scaling functions within the Green's function Monte Carlo approach. Phys. Rev. C, 96(1), 015504–12pp.
Abstract: We have studied the scaling properties of the electromagnetic response functions of He-4 and C-12 nuclei computed by the Green's function Monte Carlo approach, retaining only the one-body current contribution. Longitudinal and transverse scaling functions have been obtained in the relativistic and nonrelativistic cases and compared to experiment for various kinematics. The characteristic asymmetric shape of the scaling function exhibited by data emerges in the calculations in spite of the nonrelativistic nature of the model. The results are mostly consistent with scaling of zeroth, first, and second kinds. Our analysis reveals a direct correspondence between the scaling and the nucleon-density response functions. The scaling function obtained from the proton-density response displays scaling of the first kind, even more evidently than the longitudinal and transverse scaling functions.
|
Gambino, P., Melis, A., & Simula, S. (2017). Extraction of heavy-quark-expansion parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses. Phys. Rev. D, 96(1), 014511–17pp.
Abstract: We present a precise lattice computation of pseudoscalar and vector heavy-light meson masses for heavy-quark masses ranging from the physical charm mass up to similar or equal to 4 times the physical b-quark mass. We employ the gauge configurations generated by the European Twisted Mass Collaboration (ETMC) with N-f = 2 + 1 + 1 dynamical quarks at three values of the lattice spacing (a similar or equal to 0.062; 0.082; 0.089 fm) with pion masses in the range M-pi similar or equal to 210-450 MeV. The heavy-quark mass is simulated directly on the lattice up to similar or equal to 3 times the physical charm mass. The interpolation to the physical b-quark mass is performed using the ETMC ratio method, based on ratios of the meson masses computed at nearby heavy-quark masses, and adopting the kinetic mass scheme. The extrapolation to the physical pion mass and to the continuum limit yields m(b)(kin) (1 GeV) = 4.61(20) GeV, which corresponds to (m) over bar (b) ((m) over bar (b)) 4.26(18) GeV in the (MS) over bar scheme. The lattice data are analyzed in terms of the heavy-quark expansion (HQE) and the matrix elements of dimension-four and dimension-five operators are extracted with a good precision, namely,(Lambda) over bar = 0.552(26) GeV, mu(2)(pi) = 0.321(32) GeV2, and mu(2)(G)(m(b)) = 0.253(25) GeV2. The data also allow for a rough estimate of the dimension-six operator matrix elements. As the HQE parameters play a crucial role in the inclusive determination of the Cabibbo-Kobayashi-Maskawa matrix elements V-ub and V-cb, their precise determination on the lattice may eventually validate and improve the analyses based on fits to the semileptonic moments.
|
