Mayoral, C., Fabbri, A., & Rinaldi, M. (2011). Steplike discontinuities in Bose-Einstein condensates and Hawking radiation: Dispersion effects. Phys. Rev. D, 83(12), 124047–22pp.
Abstract: In this paper we extend the hydrodynamic results of {A. Fabbri and C. Mayoral, Phys. Rev. D 83, 124016 (2011).} and study, analytically, the propagation of Bogoliubov phonons on top of Bose-Einstein condensates with steplike discontinuities in the speed of sound by taking into account dispersion effects. We focus on the Hawking signal in the density-density correlations in the formation of acoustic blackhole-like configurations.
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BABAR Collaboration(Lees, J. P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Amplitude analysis of B0 -> K+ pi- pi0 and evidence of direct CP violation in B -> K * pi decays. Phys. Rev. D, 83(11), 112010–21pp.
Abstract: We analyze the decay B-0 -> K+ pi(-) pi(0) with a sample of 4.54 x 10(8) B (B) over bar events collected by the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC, and extract the complex amplitudes of seven interfering resonances over the Dalitz plot. These results are combined with amplitudes measured in B-0 -> K-S(0)pi(+)pi(-) decays to construct isospin amplitudes from B-0 -> K* pi and B-0 -> rho K decays. We measure the phase of the isospin amplitude Phi(3/2), useful in constraining the Cabibbo-Kobayashi-Maskawa unitarity triangle angle gamma and evaluate a CP rate asymmetry sum rule sensitive to the presence of new physics operators. We measure direct CP violation in B-0 -> K*(+) pi(-) decays at the level of 3 sigma when measurements from both B-0 -> K+ pi(-) pi(0) and B-0 -> K-S(0) pi(+) pi(-) decays are combined.
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ATLAS Collaboration(Aad, G. et al), Amoros, G., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Escobar, C., et al. (2011). Search for contact interactions in dimuon events from pp collisions at sqrt(s)=7 TeV with the ATLAS detector. Phys. Rev. D, 84(1), 011101–18pp.
Abstract: A search for contact interactions has been performed using dimuon events recorded with the ATLAS detector in proton-proton collisions at root s = 7 TeV. The data sample corresponds to an integrated luminosity of 42 pb(-1). No significant deviation from the standard model is observed in the dimuon mass spectrum, allowing the following 95% C. L. limits to be set on the energy scale of contact interactions: Lambda > 4: 9 TeV (4.5 TeV) for constructive (destructive) interference in the left-left isoscalar compositeness model. These limits are the most stringent to date for μμqq contact interactions.
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BABAR Collaboration(Lees, J. P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2011). Measurements of branching fractions and CP asymmetries and studies of angular distributions for B -> phi phi K decays. Phys. Rev. D, 84(1), 012001–13pp.
Abstract: We present branching fraction and CP asymmetry measurements as well as angular studies of B -> phi phi K decays using 464 x 10(6) B (B) over bar events collected by the BABAR experiment. The branching fractions are measured in the phi phi invariant mass range below the eta(c) resonance (m(phi phi) < 2.85 GeV). We find B(B(+) -> phi phi K(+)) = (5.6 +/- 0.5 +/- 0.3) x 10(-6) and B(B(0) -> phi phi K(0)) = (4.5 +/- 0.8 +/- 0.3) x 10(-6), where the first uncertainty is statistical and the second systematic. The measured direct CP asymmetries for the B(+/-) decays are A(CP) = -0.10 +/- 0.08 +/- 0: 02 below the eta(c) threshold (m(phi phi) < 2.85 GeV) and A(CP) = 0.09 +/- 0.10 +/- 0.02 in the eta(c) resonance region (m(phi phi) in [2.94, 3.02] GeV). Angular distributions are consistent with J(P) = 0(-) in the eta(c) resonance region and favor J(P) = 0(+) below the eta(c) resonance.
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Forero, D. V., & Guzzo, M. M. (2011). Constraining nonstandard neutrino interactions with electrons. Phys. Rev. D, 84(1), 013002–7pp.
Abstract: We update the phenomenological constraints of the nonstandard neutrino interactions (NSNI) with electrons including in the analysis, for the first time, data from LAMPF, Krasnoyarsk, and the latest Texono observations. We assume that NSNI modify the cross section of elastic scattering of (anti) neutrinos off electrons, using reactor and accelerator data, and the cross section of the electron-positron annihilation, using the four LEP experiments, in particular, new data from DELPHI. We find more restrictive allowed regions for the NSNI parameters: -0.11< epsilon(eR)(ee) < 0.05 and -0.02 < epsilon(eL)(ee) < 0.09 (90% C.L.). We also recalculate the parameters of tauonic flavor obtaining -0.35 < epsilon(eR)(tau tau) < 0.50 and -0.51 < epsilon(eL)(tau tau) < 0.34 (90% C.L.). Although more severe than the limits already present in the literature, our results indicate that NSNI are allowed by the present data as a subleading effect, and the standard electroweak model continues consistent with the experimental panorama at 90% C.L. Further improvement on this picture will deserve a lot of engagement of upcoming experiments.
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