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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Measurements of branching fractions, polarizations, and direct CP-violation asymmetries in B+ -> rho K-0*(+) and B+ -> f(0)(980)K*(+) decays. Phys. Rev. D, 83(5), 051101–8pp.
Abstract: We present measurements of the branching fractions, longitudinal polarization, and direct CP-violation asymmetries for the decays B+ -> rho K-0*(+) and B+ -> f(0)(980)K*(+) with a sample of (467 +/- 5) x 10(6)B (B) over bar pairs collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at the SLAC National Accelerator Laboratory. We observe B+ -> rho K-0*(+) with a significance of 5: 3 sigma and measure the branching fraction B(B+ -> rho K-0*(+)) = (4.6 +/- 1.0 +/- 0.4) x 10(-6), the longitudinal polarization f(L) = 0.78 +/- 0.12 +/- 0.03, and the CP-violation asymmetry A(CP) = 0.31 +/- 0.13 +/- 0.03. We observe B+ -> f(0)(980)K*(+) and measure the branching fraction B(B+ -> f(0)(980)K*(+)) x B(f(0)(980) -> pi(+)pi(-)) = (4.2 +/- 0.6 +/- 0.3) x 10(-6) and the CP-violation asymmetry A(CP) = 0.15 +/- 0.12 +/- 0.03. The first uncertainty quoted is statistical and the second is systematic.
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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2011). Measurement of neutrino-induced charged-current charged pion production cross sections on mineral oil at E-nu similar to 1 GeV. Phys. Rev. D, 83(5), 052007–26pp.
Abstract: Using a high-statistics, high-purity sample of nu(mu)-induced charged current, charged pion events in mineral oil (CH2), MiniBooNE reports a collection of interaction cross sections for this process. This includes measurements of the CC pi+ cross section as a function of neutrino energy, as well as flux-averaged single-and double-differential cross sections of the energy and direction of both the final-state muon and pion. In addition, each of the single-differential cross sections are extracted as a function of neutrino energy to decouple the shape of the MiniBooNE energy spectrum from the results. In many cases, these cross sections are the first time such quantities have been measured on a nuclear target and in the 1 GeV energy range.
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Kiesewetter, S., & Vento, V. (2010). eta-eta '-glueball mixing. Phys. Rev. D, 82(3), 034003–13pp.
Abstract: We have revisited glueball mixing with the pseudoscalar mesons in the MIT bag model scheme. The calculation has been performed in the spherical cavity approximation to the bag using two different fermion propagators, the cavity and the free propagators. We obtain probabilities of mixing for the eta at the level of 0.006%-2.0%, while for the eta' one at the level of 0.6%-40%, depending on the choice of bag radius and, therefore, of the strong coupling constant. Our results differ from previous calculations. The origin of our difference stems from the treatment of the time integrations. The comparison of our calculation with experimental data, which is consistent with small eta – eta' – G mixing, implies that the pseudoscalar glueball is small, R similar to 0.5-0.6 fm and has a large mass, M-G similar to 2000-2500 MeV.
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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Measurement of partial branching fractions of inclusive charmless B meson decays to K+, K-0, and pi(+). Phys. Rev. D, 83(3), 031103–8pp.
Abstract: We present measurements of partial branching fractions of B -> K+ X, B -> (KX)-X-0, and B -> pi(+) X, where X denotes any accessible final state above the endpoint for B decays to charmed mesons, specifically for momenta of the candidate hadron greater than 2.34 (2.36) GeV for kaons (pions) in the B rest frame. These measurements are sensitive to potential new-physics particles which could enter the b -> s(d) loop transitions. The analysis is performed on a data sample consisting of 383 X 10(6)B (B) over bar pairs collected with the BABAR detector at the PEP-II e(+)e(-) asymmetric energy collider. We observe the inclusive B -> pi(+) X process, and we set upper limits for B -> K+ X and B -> (KX)-X-0. Our results for these inclusive branching fractions are consistent with those of known exclusive modes, and exclude large enhancements due to sources of new physics.
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Lopez Honorez, L., Mena, O., & Panotopoulos, G. (2010). Higher-order coupled quintessence. Phys. Rev. D, 82(12), 123525–7pp.
Abstract: We study a coupled quintessence model in which the interaction with the dark-matter sector is a function of the quintessence potential. Such a coupling can arise from a field dependent mass term for the dark-matter field. The dynamical analysis of a standard quintessence potential coupled with the interaction explored here shows that the system possesses a late-time accelerated attractor. In light of these results, we perform a fit to the most recent Supernovae Ia, Cosmic Microwave Background, and Baryon Acoustic Oscillation data sets. Constraints arising from weak equivalence principle violation arguments are also discussed.
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Pandolfi, S., Giusarma, E., Kolb, E. W., Lattanzi, M., Melchiorri, A., Mena, O., et al. (2010). Impact of general reionization scenarios on extraction of inflationary parameters. Phys. Rev. D, 82(12), 123527–10pp.
Abstract: Determination of whether the Harrison-Zel'dovich spectrum for primordial scalar perturbations is consistent with observations is sensitive to assumptions about the reionization scenario. In light of this result, we revisit constraints on inflationary models using more general reionization scenarios. While the bounds on the tensor-to-scalar ratio are largely unmodified, when different reionization schemes are addressed, hybrid models are back into the inflationary game. In the general reionization picture, we reconstruct both the shape and amplitude of the inflaton potential. We discuss how relaxing the simple reionization restriction affects the reconstruction of the potential through the changes in the constraints on the spectral index, the tensor-to-scalar ratio and the running of the spectral index. We also find that the inclusion of other Cosmic Microwave Background data in addition to the Wilkinson Microwave Anisotropy probe data excludes the very flat potentials typical of models in which the inflationary evolution reaches a late-time attractor, as a consequence of the fact that the running of the spectral index is constrained to be different from zero at 99% confidence level.
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Carlson, E. D., Anderson, P. R., Fabbri, A., Fagnocchi, S., Hirsch, W. H., & Klyap, S. A. (2010). Semiclassical gravity in the far field limit of stars, black holes, and wormholes. Phys. Rev. D, 82(12), 124070–24pp.
Abstract: Semiclassical gravity is investigated in a large class of asymptotically flat, static, spherically symmetric spacetimes including those containing static stars, black holes, and wormholes. Specifically the stress-energy tensors of massless free spin 0 and spin 1/2 fields are computed to leading order in the asymptotic regions of these spacetimes. This is done for spin 0 fields in Schwarzschild spacetime using a WKB approximation. It is done numerically for the spin 1/2 field in Schwarzschild, extreme Reissner-Nordstrom, and various wormhole spacetimes. And it is done by finding analytic solutions to the leading order mode equations in a large class of asymptotically flat static spherically symmetric spacetimes. Agreement is shown between these various computational methods. It is found that, for all of the spacetimes considered, the energy density and pressure in the asymptotic region are proportional to r(-5) to leading order. Furthermore, for the spin 1/2 field and the conformally coupled scalar field, the stress-energy tensor depends only on the leading order geometry in the far field limit. This is also true for the minimally coupled scalar field for spacetimes containing either a static star or a black hole, but not for spacetimes containing a wormhole.
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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Analysis of the D+ -> K- pi(+) e(+) nu(e) decay channel. Phys. Rev. D, 83(7), 072001–35pp.
Abstract: Using 347: 5 fb(-1) of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244 x 10(3) signal events for the D+ -> K- pi(+)e(+)nu(e) decay channel are analyzed. This decay mode is dominated by the (K) over bar*(892)(0) contribution. We determine the (K) over bar*(892)(0) parameters: m(K*(892)0) (895.4 +/- 0.2 +/- 0.2) MeV/c(2),Gamma(0)(K*(892)0) (46.5 +/- 0.3 +/- 0.2) MeV/c(2), and the Blatt-Weisskopf parameter r(BW) = 2.1 +/- 0.5 +/- 0.5 (GeV/c)(-1), where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q(2) = 0 (r(V) = V(0)/A(1)(0) = 1.463 +/- 0.031, r(2) = A(2)(0)/A(1)(0) = 0.801 +/- 0.020 +/- 0.020) and the value of the axial-vector pole mass parametrizing the q(2) variation of A(1) and A(2): m(A) (2.63 +/- 0.10 +/- 0.13) GeV/c(2). The S-wave fraction is equal to (5.79 +/- 0.16 +/- 0: 15)%. Other signal components correspond to fractions below 1%. Using the D+ -> K-pi(+)pi(+) channel as a normalization, we measure the D+ semileptonic branching fraction: B(D+ K-pi(+)e(+)nu(e)) (4.00 +/- 0: 03 +/- 0.04 +/- 0.09) x 10(-2), where the third uncertainty comes from external inputs. We then obtain the value of the hadronic form factor A(1) at q(2) 0: A(1)(0) 0.6200 +/- 0.0056 +/- 0.0065 +/- 0.0071. Fixing the P-wave parameters, we measure the phase of the S wave for several values of the K pi mass. These results confirm those obtained with K pi production at small momentum transfer in fixed target experiments.
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Gonzalez-Alonso, M., Pich, A., & Prades, J. (2010). Pinched weights and duality violation in QCD sum rules: A critical analysis. Phys. Rev. D, 82(1), 014019–7pp.
Abstract: We analyze the so-called pinched weights, that are generally thought to reduce the violation of quarkhadron duality in finite-energy sum rules. After showing how this is not true in general, we explain how to address this question for the left-right correlator and any particular pinched weight, taking advantage of our previous work [1], where the possible high-energy behavior of the left-right spectral function was studied. In particular, we show that the use of pinched weights allows to determine with high accuracy the dimension six and eight contributions in the operator-product expansion, O-6 = (-4.3(-0.7)(+0.9)) x 10(-3) GeV6 and O-8 = (-7.2(-5.3)(+4.2)) x 10(-3) GeV8.
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BABAR Collaboration(del Amo Sanchez, P. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). B-meson decays to eta ' rho, eta ' f(0), and eta ' K*. Phys. Rev. D, 82(1), 011502–8pp.
Abstract: We present measurements of B-meson decays to the final states eta'rho, eta'f(0), and eta'K*, where K* stands for a vector, scalar, or tensor strange meson. We observe a significant signal or evidence for eta'rho(+) and all the eta'K* channels. We also measure, where applicable, the charge asymmetries, finding results consistent with no direct CP violation in all cases. The measurements are performed on a data sample consisting of 467 X 10(6) B (B) over bar pairs, collected with the BABAR detector at the PEP-II e(+)e(-) collider at the SLAC National Accelerator Laboratory. Our results favor the theoretical predictions from perturbative QCD and QCD factorization and we observe an enhancement of the tensor K-2*(1430) with respect to the vector K*(892) component.
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