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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Measurement of B (B -> Xs gamma), the B -> Xs gamma photon energy spectrum, and the direct CP asymmetry in B -> Xs+d gamma decays. Phys. Rev. D, 86(11), 112008–33pp.
Abstract: The photon spectrum in B -> X-s gamma decay, where X-s is any strange hadronic state, is studied using a data sample of (382.8 +/- 4.2) x 10(6) e(+)e(-) -> Upsilon(4S) -> B (B) over bar events collected by the BABAR experiment at the PEP-II collider. The spectrum is used to measure the branching fraction B(B -> X-s gamma) (3.21 +/- 0.15 +/- 0.29 +/- 0.08) x 10(-4) and the first, second, and third moments < E-gamma > = 2.267 +/- 0.019 +/- 0.032 +/- 0.003 GeV, <(E-gamma – < E-gamma >)(2)> = 0.0484 +/- 0.0053 +/- 0.0077 +/- 0.0005 GeV2, and <(E-gamma – < E-gamma)(3)> = -0.0048 +/- 0.0011 +/- 0.0011 +/- 0.0004 GeV3, for the range E-gamma > 1.8 GeV, where E-gamma is the photon energy in the B-meson rest frame. Results are also presented for narrower E-gamma ranges. In addition, the direct CP asymmetry A(CP)(B -> Xs+d gamma) is measured to be 0.057 +/- 0.063. The spectrum itself is also unfolded to the B-meson rest frame; that is the frame in which theoretical predictions for its shape are made.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Measurement of the time-dependent CP asymmetry of partially reconstructed B-0 -> D*D+*(-) decays. Phys. Rev. D, 86(11), 112006–15pp.
Abstract: We present a new measurement of the time-dependent CP asymmetry of B-0 -> D*D+*(-) decays using (471 +/- 5) million B (B) over bar pairs collected with the BABAR detector at the PEP-II B Factory at the SLAC National Accelerator Laboratory. Using the technique of partial reconstruction, we measure the time-dependent CP asymmetry parameters S = -0.34 +/- 0.12 +/- 0.05 and C = 0.15 +/- 0.09 +/- 0.04. Using the value for the CP-odd fraction R-perpendicular to = 0.158 +/- 0.028 +/- 0.006, previously measured by BABAR with fully reconstructed B-0 -> D*D+*(-) events, we extract the CP-even components S+ = 0.49 +/- 0.18 +/- 0.07 +/- 0.04 and C+ = +0.15 +/- 0.09 +/- 0.04. In each case, the first uncertainty is statistical and the second is systematic; the third uncertainty on S+ is the contribution from the uncertainty on R-perpendicular to. The measured value of the CP-even component S+ is consistent with the value of sin2 beta measured in b -> (c (c) over bar )s transitions, and with the Standard Model expectation of small penguin contributions.
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Botella-Soler, V., & Glendinning, P. (2012). Emergence of hierarchical networks and polysynchronous behaviour in simple adaptive systems. EPL, 97(5), 50004–5pp.
Abstract: We describe the dynamics of a simple adaptive network. The network architecture evolves to a number of disconnected components on which the dynamics is characterized by the possibility of differently synchronized nodes within the same network (polysynchronous states). These systems may have implications for the evolutionary emergence of polysynchrony and hierarchical networks in physical or biological systems modeled by adaptive networks.
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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). Measurement of the ZZ Production Cross Section and Limits on Anomalous Neutral Triple Gauge Couplings in Proton-Proton Collisions at root s=7 TeV with the ATLAS Detector. Phys. Rev. Lett., 108(4), 041804–18pp.
Abstract: A measurement of the ZZ production cross section in proton-proton collisions at root s = 7 TeV using data corresponding to an integrated luminosity of 1.02 fb(-1) recorded by the ATLAS experiment at the LHC is presented. Twelve events containing two Z boson candidates decaying to electrons and/or muons are observed, with an expected background of 0.3 +/- 0.3(stat)(-0.3)(+0.4)(syst) events. The cross section measured in a phase-space region with good detector acceptance and for dilepton masses within the range 66 to 116 GeV is sigma(fid)(ZZ -> l+l-l+l-) = 19.4(-5.2)(+6.3)(stat)(-0.7)(+0.9)(syst) +/- 0.7(lumi) fb. The resulting total cross section for on-shell ZZ production, sigma(tot)(ZZ) = 8.5(-2.3)(+2.7)(stat)(-0.3)(+0.4)(syst) +/- 0.3(lumi) pb, is consistent with the standard model expectation of 6.5(-0.2)(+0.3) pb calculated at the next-to-leading order in QCD. Limits on anomalous neutral triple gauge boson couplings are derived.
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Iocco, F., Taoso, M., Leclercq, F., & Meynet, G. (2012). Main Sequence Stars with Asymmetric Dark Matter. Phys. Rev. Lett., 108(6), 061301–5pp.
Abstract: We study the effects of feebly or nonannihilating weakly interacting dark matter (DM) particles on stars that live in DM environments denser than that of our Sun. We find that the energy transport mechanism induced by DM particles can produce unusual conditions in the cores of main sequence stars, with effects which can potentially be used to probe DM properties. We find that solar mass stars placed in DM densities of rho(chi) >= 10(2) GeV/cm(3) are sensitive to spin-dependent scattering cross section sigma(SD) >= 10(-37) cm(2) and a DM particle mass as low as m(chi) = 5 GeV, accessing a parameter range weakly constrained by current direct detection experiments.
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