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BABAR Collaboration(Lees, J. P. et al), Lopez-March, N., Martinez-Vidal, F., & Oyanguren, A. (2012). Search for the decay D-0 -> gamma gamma and measurement of the branching fraction for D-0 -> pi(0)pi(0). Phys. Rev. D, 85(9), 091107–8pp.
Abstract: We search for the rare decay of the D-0 meson to two photons, D-0 -> gamma gamma, and present a measurement of the branching fraction for a D-0 meson decaying to two neutral pions, B(D-0 -> pi(0)pi(0)). The data sample analyzed corresponds to an integrated luminosity of 470.5 fb(-1) collected by the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at SLAC. We place an upper limit on the branching fraction, B(D-0 -> gamma gamma) < 2.2 x 10(-6), at 90% confidence level. This limit improves on the existing limit by an order of magnitude. We also find B(D-0 -> pi(0)pi(0)) = (8.4 +/- 0.1 +/- 0.4 +/- 0.3 +/-) x 10(-4).
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n_TOF Collaboration(Gunsing, F. et al), Domingo-Pardo, C., & Tain, J. L. (2012). Measurement of resolved resonances of Th-232(n, gamma) at the n_TOF facility at CERN. Phys. Rev. C, 85(6), 064601–17pp.
Abstract: The yield of the neutron capture reaction Th-232(n, gamma) has been measured at the neutron time-of-flight facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The reduction of the acquired data to the capture yield for resolved resonances from 1 eV to 4 keV is described and compared to a recent evaluated data set. The resonance parameters were used to assign an orbital momentum to each resonance. A missing level estimator was used to extract the s-wave level spacing of D-0 = 17.2 +/- 0.9 eV.
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Aguilar-Saavedra, J. A., Deppisch, F., Kittel, O., & Valle, J. W. F. (2012). Flavor in heavy neutrino searches at the LHC. Phys. Rev. D, 85(9), 091301–4pp.
Abstract: Heavy neutrinos at the TeV scale have been searched for at the LHC in the context of left-right models, under the assumption that they couple to the electron, the muon, or both. We show that current searches are also sensitive to heavy neutrinos coupling predominantly to the tau lepton, and present limits can significantly constrain the parameter space of general flavor mixing.
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Recchia, F. et al, & Gadea, A. (2012). Spectroscopy of odd-mass cobalt isotopes toward the N=40 subshell closure and shell-model description of spherical and deformed states. Phys. Rev. C, 85(6), 064305–10pp.
Abstract: The neutron-rich cobalt isotopes up to A = 67 have been studied through multinucleon transfer reactions by bombarding a U-238 target with a 460-MeV Zn-70 beam. Unambiguous identification of prompt gamma rays belonging to each nucleus has been achieved using coincidence relationships with the ions detected in a high-acceptance magnetic spectrometer. The new data are discussed in terms of the systematics of the cobalt isotopes and interpreted with large-scale shell-model calculations in the fpgd model space. In particular, very different shapes can be described in Co-67, at the edge of the island of inversion at N = 40, where a low-lying highly deformed band coexists with a spherical structure.
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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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