Fernandez-Carames, T., Valcarce, A., & Vijande, J. (2010). Charged charmonium molecules. Phys. Rev. D, 82(5), 054032–5pp.
Abstract: We make use of a self-consistent quark-model based study of four-quark charmonium-like states to interpret recent charmonium experimental data. We conclude that there exists a D*(D) over bar* meson-meson molecule with quantum numbers (I-G) J(PC) = (1(-))2(++). Our study confirms the presence of charged charmonium-like resonances on the excited charmonium spectrum. We find support from recent experimental data by the Belle Collaboration [R. Mizuk et al. (Belle Collaboration), Phys. Rev. D 78, 072004 (2008)]. Confirmation of the experimental data by the Belle Collaboration and the determination of the quantum numbers of the new structures would help in discriminating among different theoretical models and would give further support to the theoretical analysis of T. Fernandez-Carames, A. Valcarce, and J. Vijande [Phys. Rev. Lett. 103, 222001 (2009)].
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de Campos, F., Eboli, O. J. P., Hirsch, M., Magro, M. B., Porod, W., Restrepo, D., et al. (2010). Probing neutrino oscillations in supersymmetric models at the Large Hadron Collider. Phys. Rev. D, 82(7), 075002–8pp.
Abstract: The lightest supersymmetric particle may decay with branching ratios that correlate with neutrino oscillation parameters. In this case the CERN Large Hadron Collider (LHC) has the potential to probe the atmospheric neutrino mixing angle with sensitivity competitive to its low-energy determination by underground experiments. Under realistic detection assumptions, we identify the necessary conditions for the experiments at CERN's LHC to probe the simplest scenario for neutrino masses induced by minimal supergravity with bilinear R parity violation.
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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Measurement of CP observables in B-+/- -> DCPK +/- decays and constraints on the CKM angle gamma. Phys. Rev. D, 82(7), 072004–20pp.
Abstract: Using the entire sample of 467 x 10(6) Y(4S) -> B (B) over bar decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory, we perform an analysis of B-+/- -> DK +/- decays, using decay modes in which the neutral D meson decays to either CP-eigenstates or non-CP-eigenstates. We measure the partial decay rate charge asymmetries for CP-even and CP-odd D final states to be A(CP+) = 0.25 +/- 0.06 +/- 0.02 and A(CP-) = 0.09 +/- 0.07 +/- 0.02, respectively, where the first error is the statistical and the second is the systematic uncertainty. The parameter A(CP+) is different from zero with a significance of 3.6 standard deviations, constituting evidence for direct CP violation. We also measure the ratios of the charged-averaged B partial decay rates in CP and non-CP decays, RCP+ 1.18 +/- 0.09 +/- 0.05 and RCP- = 1.07 +/- 0.08 +/- 0.04. We infer frequentist confidence intervals for the angle gamma of the unitarity triangle, for the strong phase difference delta(B), and for the amplitude ratio r(B), which are related to the B- -> DK- decay amplitude by r(B)e(i(delta B-gamma)) = A(B- -> (D) over bar K-0(-)) = A(B- -> (D) over bar K-0(-))/A(B- -> (DK-)-K-0). Including statistical and systematic uncertainties, we obtain 0: 24 < rB < 0: 45 ( 0: 06 < rB < 0: 51) and, modulo 180 degrees, 11.3 degrees < gamma < 22.7 degrees or 80.8 degrees < gamma < 99.2 degrees or 157.3 degrees < gamma < 168.7 degrees (7.0 degrees < gamma < 173.0 degrees) at the 68% ( 95%) confidence level.
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Taoso, M., Iocco, F., Meynet, G., Bertone, G., & Eggenberger, P. (2010). Effect of low mass dark matter particles on the Sun. Phys. Rev. D, 82(8), 083509–14pp.
Abstract: We study the effect of dark matter (DM) particles in the Sun, focusing, in particular, on the possible reduction of the solar neutrinos flux due to the energy carried away by DM particles from the innermost regions of the Sun, and to the consequent reduction of the temperature of the solar core. We find that in the very low-mass range between 4 and 10 GeV, recently advocated to explain the findings of the DAMA and CoGent experiments, the effects on neutrino fluxes are detectable only for DM models with a very small, or vanishing, self-annihilation cross section, such as the so-called asymmetric DM models, and we study the combination of DM masses and spin-dependent cross sections which can be excluded with current solar neutrino data. Finally, we revisit the recent claim that DM models with large self-interacting cross sections can lead to a modification of the position of the convective zone, alleviating or solving the solar composition problem. We show that when the "geometric'' upper limit on the capture rate is correctly taken into account, the effects of DM are reduced by orders of magnitude, and the position of the convective zone remains unchanged.
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Geng, L. S., Kaiser, N., Martin Camalich, J., & Weise, W. (2010). Low-energy interactions of Nambu-Goldstone bosons with D mesons in covariant chiral perturbation theory. Phys. Rev. D, 82(5), 054022–7pp.
Abstract: We calculate the scattering lengths of Nambu-Goldstone bosons interacting with D mesons in a covariant formulation of chiral perturbation theory, which satisfies heavy-quark spin symmetry and analytical properties of loop amplitudes. We compare our results with previous studies performed using heavy-meson chiral perturbation theory and show that recoil corrections are sizable in most cases.
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