BABAR Collaboration(del Amo Sanchez, P. et al), Azzolini, V., Lopez-March, N., Martinez-Vidal, F., Milanes, D. A., & Oyanguren, A. (2010). Search for CP violation using T-odd correlations in D-0 -> K+K-pi(+)pi(-) decays. Phys. Rev. D, 81(11), 111103–8pp.
Abstract: We search for CP violation in a sample of 4.7 x 10(4) Cabibbo suppressed D-0 -> K+K-pi(+)pi(-) decays. We use 470 fb(-1) of data recorded by the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) storage rings running at center-of-mass energies near 10.6 GeV. CP violation is searched for in the difference between the T-odd asymmetries, obtained using triple product correlations, measured for D-0 and (D) over bar (0) decays. The measured CP violation parameter is A(T) = (1.0 +/- 5.1(stat) +/- 4.4(syst)) x 10(-3).
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Giordano, G., Mena, O., & Mocioiu, I. (2010). Atmospheric neutrino oscillations and tau neutrinos in ice. Phys. Rev. D, 81(11), 113008–5pp.
Abstract: The main goal of the IceCube Deep Core Array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show here that cascade measurements in the Ice Cube Deep Core Array can provide strong evidence for tau neutrino appearance in atmospheric neutrino oscillations. Controlling systematic uncertainties will be the limiting factor in the analysis. A careful study of these tau neutrinos is crucial, since they constitute an irreducible background for astrophysical neutrino detection.
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Aguilar, A. C., Binosi, D., & Papavassiliou, J. (2010). Nonperturbative gluon and ghost propagators for d=3 Yang-Mills theory. Phys. Rev. D, 81(12), 125025–13pp.
Abstract: We study a manifestly gauge-invariant set of Schwinger-Dyson equations to determine the non-perturbative dynamics of the gluon and ghost propagators in d = 3 Yang-Mills theory. The use of the well-known Schwinger mechanism, in the Landau gauge leads to the dynamical generation of a mass for the gauge boson (gluon in d = 3), which, in turn, gives rise to an infrared finite gluon propagator and ghost dressing function. The propagators obtained from the numerical solution of these nonperturbative equations are in very good agreement with the results of SU(2) lattice simulations.
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CDF Collaboration(Aaltonen, T. et al), Cabrera, S., & Cuenca Almenar, C. (2010). Search for Pair Production of Supersymmetric Top Quarks in Dilepton Events from p(p)over-bar Collisions at root s=1.96 TeV. Phys. Rev. Lett., 104(25), 251801–8pp.
Abstract: We present the results of a search for pair production of the supersymmetric partner of the top quark (the top squark (t) over tilde (1)) decaying to a b quark and a chargino (chi) over tilde (+/-)(1) with a subsequent (chi) over tilde (+/-)(1) decay into a neutralino (chi) over tilde (0)(1), lepton l, and neutrino nu Using a data sample corresponding to 2.7 fb(-1) of integrated luminosity of p (p) over bar collisions at root s = 1: 96 TeV collected by the CDF II detector, we reconstruct the mass of top squark candidate events and fit the observed mass spectrum to a combination of standard model processes and (t) over tilde (1)(t) over tilde (1). We find no evidence for (t) over tilde (1)(t) over tilde (1) production and set 95% C. L. limits on the masses of the top squark and the neutralino for several values of the chargino mass and the branching ratio B((X) over tilde (+/-)(1) -> (chi) over tilde (0)(1)l(+/-)nu).
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Cheng, Y., Csernai, L. P., Magas, V. K., Schlei, B. R., & Strottman, D. (2010). Matching stages of heavy-ion collision models. Phys. Rev. C, 81(6), 064910–8pp.
Abstract: Heavy-ion reactions and other collective dynamical processes are frequently described by different theoretical approaches for the different stages of the process, like initial equilibration stage, intermediate locally equilibrated fluid dynamical stage, and final freeze-out stage. For the last stage, the best known is the Cooper-Frye description used to generate the phase space distribution of emitted, noninteracting particles from a fluid dynamical expansion or explosion, assuming a final ideal gas distribution, or (less frequently) an out-of-equilibrium distribution. In this work we do not want to replace the Cooper-Frye description, but rather clarify the ways of using it and how to choose the parameters of the distribution and, eventually, how to choose the form of the phase space distribution used in the Cooper-Frye formula. Moreover, the Cooper-Frye formula is used in connection with the freeze-out problem, while the discussion of transition between different stages of the collision is applicable to other transitions also. More recently, hadronization and molecular dynamics models have been matched to the end of a fluid dynamical stage to describe hadronization and freeze-out. The stages of the model description can be matched to each other on space-time hypersurfaces (just like through the frequently used freeze-out hypersurface). This work presents a generalized description of how to match the stages of the description of a reaction to each other, extending the methodology used at freeze-out, in simple covariant form which is easily applicable in its simplest version for most applications.
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