Sun, B. X., Garzon, E. J., & Oset, E. (2010). Radiative decay into gamma-baryon of dynamically generated resonances from the vector-baryon interaction. Phys. Rev. D, 82(3), 034028–11pp.
Abstract: We study the radiative decay into gamma and a baryon of the SU(3) octet and decuplet of nine and ten resonances that are dynamically generated from the interaction of vector mesons with baryons of the octet and the decuplet, respectively. We obtain quite different partial decay widths for the various resonances, and for different charge states of the same resonance, suggesting that the experimental investigation of these radiative decays should bring much information on the nature of these resonances. For the case of baryons of the octet we determine the helicity amplitudes and compare them with experimental data when available.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Search for anomalous production of events with two photons and additional energetic objects at CDF. Phys. Rev. D, 82(5), 052005–27pp.
Abstract: We present results of a search for anomalous production of two photons together with an electron, muon, tau lepton, missing transverse energy, or jets using p (p) over bar collision data from 1.1-2.0 fb(-1) of integrated luminosity collected by the Collider Detector at Fermilab (CDF). The event yields and kinematic distributions are examined for signs of new physics without favoring a specific model of new physics. The results are consistent with the standard model expectations. The search employs several new analysis
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Constantinou, M., Dimopoulos, P., Frezzotti, R., Jansen, K., Gimenez, V., Lubicz, V., et al. (2011). B-K-parameter from N-f=2 twisted mass lattice QCD. Phys. Rev. D, 83(1), 014505–20pp.
Abstract: We present an unquenched N-f = 2 lattice computation of the B-K parameter which controls K-0 – (K) over bar (0) oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the B-K parameter which is both multiplicatively renormalizable and O(a) improved. Employing the nonperturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get B-K(RGI) = 0.729 +/- 0.030, a number well in line with the existing quenched and unquenched determinations.
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Yamagata-Sekihara, J., Roca, L., & Oset, E. (2010). Nature of the K-2*(1430), K-3*(1780), K-4*(2045), K-5*(2380), and K-6* as K*-multi-rho states. Phys. Rev. D, 82(9), 094017–8pp.
Abstract: We show that the K-2*(1430), K-3*(1780), K-4*(2045), K-5*(2380), and a not-yet-discovered K-6* resonance are basically molecules made of an increasing number of rho(770) and one K*(892) mesons. The idea relies on the fact that the vector-vector interaction in the s wave with spins aligned is very strong for both rho rho and K*rho. We extend a recent work, where several resonances showed up as multi-rho(770) molecules, to the strange sector including the K*(892) into the system. The resonant structures show up in the multibody scattering amplitudes, which are evaluated in terms of the unitary two-body vector-vector scattering amplitudes by using the fixed center approximation to the Faddeev equations.
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BABAR Collaboration(Lees, J. P. et al), Martinez-Vidal, F., & Oyanguren, A. (2011). Observation of the baryonic B decay (B)over-bar(0) -> Lambda(+)(c)(Lambda)over-barK(-). Phys. Rev. D, 84(7), 071102–7pp.
Abstract: We report the observation of the baryonic B decay (B) over bar (0) -> Lambda(+)(c)Lambda K(-) with a significance larger than 7 standard deviations based on 471 x 10(6) B (B) over bar pairs collected with the BABAR detector at the PEP-II storage ring at SLAC. We measure the branching fraction for the decay (B) over bar (0) -> Lambda(+)(c)Lambda K(-) to be (3.8 +/- 0.8(stat) +/- 0.2(sys) +/- 1.0(Lambda c)(+)) x 10(-5). The uncertainties are statistical, systematic, and due to the uncertainty in the Lambda(+)(c) branching fraction. We find that the Lambda(+)(c)K(-) invariant-mass distribution shows an enhancement above 3.5 GeV/c(2).
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