CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Updated search for the flavor-changing neutral-current decay D-0 -> mu(+)mu(-) in p(p)over-bar collisions at root s=1.96 TeV. Phys. Rev. D, 82(9), 091105–8pp.
Abstract: We report on a search for the flavor-changing neutral-current decay D-0 -> mu(+)mu(-) in p (p) over bar collisions at root s = 1.96 TeV using 360 pb(-1) of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D-0 candidates in the mu(+)mu(-), pi(+)pi(-), and K-pi(+) decay modes. We use the Cabibbo-favored D-0 -> K-pi(+) channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D-0 -> pi(+)pi(-) channel for normalization. We set an upper limit on the branching fraction B(D-0 -> mu(+)mu(-)) < 2.1 X 10(-7) (3.0 X 10(-7)) at the 90% (95%) confidence level.
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Fogli, G. L., Lisi, E., Palazzo, A., & Rotunno, A. M. (2010). Combined analysis of KamLAND and Borexino neutrino signals from Th and U decays in the Earth's interior. Phys. Rev. D, 82(9), 093006–9pp.
Abstract: The KamLAND and Borexino experiments have detected electron antineutrinos produced in the decay chains of natural thorium and uranium (Th and U geoneutrinos). We analyze the energy spectra of current geoneutrino data in combination with solar and long-baseline reactor neutrino data, with marginalized three-neutrino oscillation parameters. We consider the case with unconstrained Th and U event rates in KamLAND and Borexino, as well as cases with fewer degrees of freedom, as obtained by successively assuming for both experiments a common Th/U ratio, a common scaling of Th + U event rates, and a chondritic Th/U value. In combination, KamLAND and Borexino can reject the null hypothesis (no geoneutrino signal) at 5 sigma. Interesting bounds or indications emerge on the Th + U geoneutrino rates and on the Th/U ratio, in broad agreement with typical Earth model expectations. Conversely, the results disfavor the hypothesis of a georeactor in the Earth's core, if its power exceeds a few TW. The interplay of KamLAND and Borexino geoneutrino data is highlighted.
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Staub, F., Porod, W., & Herrmann, B. (2010). The electroweak sector of the NMSSM at the one-loop level. J. High Energy Phys., 10(10), 040–50pp.
Abstract: We present the electroweak spectrum for the Next-to-Minimal Supersymmetric Standard Model at the one-loop level, e. g. the masses of Higgs bosons, sleptons, charginos and neutralinos. For the numerical evaluation we present a mSUGRA variant with non-universal Higgs mass parameters squared and we compare our results with existing ones in the literature. Moreover, we briefly discuss the implications of our results for the calculation of the relic density.
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Bierenbaum, I., Catani, S., Draggiotis, P., & Rodrigo, G. (2010). A tree-loop duality relation at two loops and beyond. J. High Energy Phys., 10(10), 073–22pp.
Abstract: The duality relation between one-loop integrals and phase-space integrals, developed in a previous work, is extended to higher-order loops. The duality relation is realized by a modification of the customary +i0 prescription of the Feynman propagators, which compensates for the absence of the multiple-cut contributions that appear in the Feynman tree theorem. We rederive the duality theorem at one-loop order in a form that is more suitable for its iterative extension to higher-loop orders. We explicitly show its application to two-and three-loop scalar master integrals, and we discuss the structure of the occurring cuts and the ensuing results in detail.
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Bizzeti, P. G. et al, & Gadea, A. (2010). Transition probabilities in the X(5) candidate Ba-122. Phys. Rev. C, 82(5), 054311–10pp.
Abstract: To investigate the possible X(5) character of Ba-122, suggested by the ground-state band energy pattern, the lifetimes of the lowest yrast states of Ba-122 have been measured, via the recoil distance Doppler-shift method. The relevant levels have been populated by using the Cd-108(O-16,2n)Ba-122 and the Sn-112(C-13, 3n)Ba-122 reactions. The B(E2) values deduced in the present work are compared to the predictions of the X(5) model and to calculations performed in the framework of the IBA-1 and IBA-2 models.
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