Pi, M., Barranco, M., Navarro, J., & Ancilotto, F. (2012). Nucleation and cavitation in parahydrogen. Chem. Phys., 399, 213–217.
Abstract: We have used a density functional approach to investigate thermal homogeneous nucleation and cavitation in parahydrogen. The effect of electrons as seeds of heterogeneous cavitation in liquid parahydrogen is also discussed within the capillary model.
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Ledwig, T., Martin-Camalich, J., Pascalutsa, V., & Vanderhaeghen, M. (2012). Nucleon and Delta(1232) form factors at low momentum transfer and small pion masses. Phys. Rev. D, 85(3), 034013–25pp.
Abstract: An expansion of the electromagnetic form factors of the nucleon and Delta(1232) in small momentum transfer and pion mass is performed in a manifestly covariant EFT framework consistent with chiral symmetry and analyticity. We present the expressions for the nucleon and Delta(1232) electromagnetic form factors, charge radii, and electromagnetic moments in the framework of SU(2) baryon chiral perturbation theory, with nucleon and Delta-isobar degrees of freedom, to next-to-leading order. Motivated by the results for the proton electric radius obtained from the muonic-hydrogen atom and electron-scattering process, we extract values for the second derivative of the electric form factor which is a genuine prediction of the p(3) B chi PT. The chiral behavior of radii and moments is studied and compared to that obtained in the heavy-baryon framework and lattice QCD. The chiral behavior of Delta(1232)-isobar properties exhibits cusps and singularities at the threshold of Delta -> pi N decay, and their physical significance is discussed.
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BABAR Collaboration(del Amo Sanchez, P. et al), Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2012). Observation and study of the baryonic B-meson decays B -> D(*) p(p)over-bar (pi)(pi). Phys. Rev. D, 85(9), 092017–21pp.
Abstract: We present results for B-meson decay modes involving a charm meson, protons, and pions using 455 x 10(6) B (B) over bar pairs recorded by the BaBar detector at the SLAC PEP-II asymmetric-energy e(+)e(-) collider. The branching fractions are measured for the following ten decays: (B) over bar (0) -> D-0 p (p) over bar, (B) over bar (0) -> D*(0) p (p) over bar, (B) over bar (0) -> D+ p (p) over bar pi(-) , (B) over bar (0) -> D-0 p (p) over bar pi(-) , B- -> D-0 p (p) over bar pi(-) , B- -> D*(0) p (p) over bar pi(-) , (B) over bar (0) -> D-0 p (p) over bar pi(-) pi(+) , (B) over bar (0) -> D*(0) p (p) over bar pi(-) pi(+) B- -> D+ p (p) over bar pi(-) pi(-) , and B- -> D*(0) p (p) over bar pi(-) pi(-). The four B- and the two five-body (B) over bar (0) modes are observed for the first time. The four-body modes are enhanced compared to the three- and the five-body modes. In the three-body modes, the M(p (p) over bar) and M(D-(*)0 p) invariant- mass distributions show enhancements near threshold values. In the four-body mode (B) over bar (0) -> D+ p (p) over bar pi(-) , the M(p pi(-)) distribution shows a narrow structure of unknown origin near 1: 5 GeV/c(2). The distributions for the five-body modes, in contrast to the others, are similar to the expectations from uniform phase-space predictions.
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ATLAS Collaboration(Aad, G. et al), Amoros, G., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Ferrer, A., et al. (2012). Observation of a New chi(b) State in Radiative Transitions to Y(1S) and Y(2S) at ATLAS. Phys. Rev. Lett., 108(15), 152001–17pp.
Abstract: The chi(b)(np) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider at root s=7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb(-1), these states are reconstructed through their radiative decays to Y(1S,2S) with Y ->mu(+)mu(-). In addition to the mass peaks corresponding to the decay modes chi(b)(1P,2P)-> Y(1S)gamma, a new structure centered at a mass of 10.530 +/- 0.005(stat)+/- 0.009(syst) GeV is also observed, in both the Y(1S)gamma and Y(2S)gamma decay modes. This structure is interpreted as the chi(b)(3P) system.
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ATLAS Collaboration(Aad, G. et al), Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Ferrer, A., Fiorini, L., et al. (2012). Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC. Phys. Lett. B, 716(1), 1–29.
Abstract: A search for the Standard Model Higgs boson in proton-proton collisions with the ATLAS detector at the LHC is presented. The datasets used correspond to integrated luminosities of approximately 4.8 fb(-1) collected at, root s = 7 TeV in 2011 and 5.8 fb(-1) at root s = 8 TeV in 2012. Individual searches in the channels H -> ZZ(()*()) -> 4l, H -> gamma gamma and H -> WW (()*()) -> ev μv in the 8 TeV data are combined with previously published results of searches for H -> ZZ(()*()), WW(*()), b (b) over bar and tau(+)tau(-) in the 7 TeV data and results from improved analyses of the H -> ZZ(()*()) -> 4l and H -> gamma gamma channels in the 7 TeV data. Clear evidence for the production of a neutral boson with a measured mass of 126.0 +/- 0.4 (stat) +/- 0.4 (sys) GeV is presented. This observation, which has a significance of 5.9 standard deviations, corresponding to a background fluctuation probability of 1.7 x 10(-9), is compatible with the production and decay of the Standard Model Higgs boson. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.
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