BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2012). Study of CP violation in Dalitz-plot analyses of B-0 -> K+ K- K-s(0), B+ -> K+ K- K+, and B+ -> (KsKsK+)-K-0-K-0. Phys. Rev. D, 85(11), 112010–31pp.
Abstract: We perform amplitude analyses of the decays B-0 -> K+ K- K-s(0), B+ -> K+ K- K+, and B+ -> K-s(0) K-s(0) K+, and measure CP-violating parameters and partial branching fractions. The results are based on a data sample of approximately 470 x 10(6) B (B) over bar decays, collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory. For B+ -> K+ K- K+, we find a direct CP asymmetry in B+ -> phi(1020)K+ of A(CP) = (12.8 +/- 4.4 +/- 1.3)%, which differs from zero by 2.8 sigma. For B-0 -> K+ K- K-s(0), we measure the CP-violating phase ss(eff)(phi(1020)K-s(0)) = (21 +/- 6 +/- 2)degrees. For B+ -> K-s(0) K-s(0) K+, we measure an overall direct CP asymmetry of A(CP) = (4(-5)(+4) +/- 2)%. We also perform an angular-moment analysis of the three channels and determine that the f(X()1500) state can be described well by the sum of the resonances f(0)(1500), f(2)'(1525), and f(0)(1710).
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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). Search for a Light Higgs Boson Decaying to Long-Lived Weakly Interacting Particles in Proton-Proton Collisions at root s=7 TeV with the ATLAS Detector. Phys. Rev. Lett., 108(25), 251801–18pp.
Abstract: A search for the decay of a light Higgs boson (120-140 GeV) to a pair of weakly interacting, long-lived particles in 1.94 fb(-1) of proton-proton collisions at root s = 7 TeV recorded in 2011 by the ATLAS detector is presented. The search strategy requires that both long-lived particles decay inside the muon spectrometer. No excess of events is observed above the expected background and limits on the Higgs boson production times branching ratio to weakly interacting, long-lived particles are derived as a function of the particle proper decay length.
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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). Search for resonant WZ production in the WZ -> lvl ' l ' channel in root(s)=7 TeV pp collisions with the ATLAS detector. Phys. Rev. D, 85(11), 112012–21pp.
Abstract: A generic search is presented for a heavy particle decaying to WZ -> lvl'l' (l, l' = e, mu) final states. The data were recorded by the ATLAS detector in root s = 7 TeV pp collisions at the Large Hadron Collider and correspond to an integrated luminosity of 1.02 fb(-1). The transverse mass distribution of the selected WZ candidates is found to be consistent with the standard model expectation. Upper limits on the production cross section times branching ratio are derived using two benchmark models predicting a heavy particle decaying to a WZ pair.
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Baker, M. J., Bordes, J., Hong-Mo, C., & Tsun, T. S. (2012). Developing the Framed Standard Model. Int. J. Mod. Phys. A, 27(17), 1250087–45pp.
Abstract: The framed standard model (FSM) suggested earlier, which incorporates the Higgs field and three fermion generations as part of the framed gauge theory (FGT) structure, is here developed further to show that it gives both quarks and leptons hierarchical masses and mixing matrices akin to what is experimentally observed. Among its many distinguishing features which lead to the above results are (i) the vacuum is degenerate under a global su(3) symmetry which plays the role of fermion generations, (ii) the fermion mass matrix is “universal,” rank-one and rotates (changes its orientation in generation space) with changing scale mu, (iii) the metric in generation space is scale-dependent too, and in general nonflat, (iv) the theta-angle term in the quantum chromodynamics (QCD) action of topological origin gets transformed into the CP-violating phase of the Cabibbo-Kobayashi-Maskawa (CKM) matrix for quarks, thus offering at the same time a solution to the strong CP problem.
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Hirsch, M., Staub, F., & Vicente, A. (2012). Enhancing l(i) -> 3l(j) with the Z(0)-penguin. Phys. Rev. D, 85(11), 113013–5pp.
Abstract: Lepton flavor violation has been observed in neutrino oscillations. For charged lepton flavor violation decays only upper limits are known, but sizable branching ratios are expected in many neutrino mass models. High-scale models, such as the classical supersymmetric seesaw, usually predict that decays l(i) -> 3l(j) are roughly a factor alpha smaller than the corresponding decays l(i) -> l(j)gamma. Here we demonstrate that the Z(0)-penguin diagram can give an enhancement for decays l(i) -> 3l(j) in many extensions of the minimal supersymmetric standard model (MSSM). We first discuss why the Z(0)-penguin is not dominant in the MSSM with seesaw and show that much larger contributions from the Z(0)-penguin are expected in general. We then demonstrate the effect numerically in two example models, namely, the supersymmetric inverse seesaw and R-parity violating supersymmetry.
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