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Rafi Alam, M., Ruiz Simo, I., Sajjad Athar, M., & Vicente Vacas, M. J. (2010). Weak kaon production off the nucleon. Phys. Rev. D, 82(3), 033001–8pp.
Abstract: The weak kaon production off the nucleon induced by neutrinos is studied at the low and intermediate energies of interest for some ongoing and future neutrino oscillation experiments. This process is also potentially important for the analysis of proton decay experiments. We develop a microscopical model based on the SU(3) chiral Lagrangians. The basic parameters of the model are f pi, the pion decay constant, Cabibbo's angle, the proton and neutron magnetic moments, and the axial vector coupling constants for the baryons octet, D and F, that are obtained from the analysis of the semileptonic decays of neutron and hyperons. The studied mechanisms are the main source of kaon production for neutrino energies up to 1.2 to 1.5 GeV for the various channels and the cross sections are large enough to be amenable to be measured by experiments such as Minerva and T2K.
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Barenboim, G., & Panotopoulos, G. (2010). Gravitino dark matter in the constrained next-to-minimal supersymmetric standard model with neutralino next-to-lightest superpartner. J. High Energy Phys., 09, 011–20pp.
Abstract: The viability of a possible cosmological scenario is investigated. The theoretical framework is the constrained next-to-minimal supersymmetric standard model (cNMSSM), with a gravitino playing the role of the lightest supersymmetric particle (LSP) and a neutralino acting as the next-to-lightest supersymmetric particle (NLSP). All the necessary constraints from colliders and cosmology have been taken into account. For gravitino we have considered the two usual production mechanisms, namely out-of equillibrium decay from the NLSP, and scattering processes from the thermal bath. The maximum allowed reheating temperature after inflation, as well as the maximum allowed gravitino mass are determined.
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Catford, W. N. et al, Caballero, L., & Rubio, B. (2010). Migration of Nuclear Shell Gaps Studied in the d(Ne-24, p gamma)Ne-25 Reaction. Phys. Rev. Lett., 104(19), 192501–4pp.
Abstract: The transfer of neutrons onto Ne-24 has been measured using a reaccelerated radioactive beam of Ne-24 to study the (d, p) reaction in inverse kinematics. The unusual raising of the first 3/2(+) level in Ne-25 and its significance in terms of the migration of the neutron magic number from N = 20 to N = 16 is put on a firm footing by confirmation of this state's identity. The raised 3/2(+) level is observed simultaneously with the intruder negative parity 7/2(-) and 3/2(-) levels, providing evidence for the reduction in the N = 20 gap. The coincident gamma-ray decays allowed the assignment of spins as well as the transferred orbital angular momentum. The excitation energy of the 3/2(+) state shows that the established USD shell model breaks down well within the sd model space and requires a revised treatment of the proton-neutron monopole interaction.
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Xie, J. J., & Wilkin, C. (2010). Associated strangeness production in the pp -> pK(+) K(-)p and pp -> pK(+)pi(0)Sigma(0) reactions. Phys. Rev. C, 82(2), 025210–6pp.
Abstract: The total and differential cross sections for associated strangeness production in the pp -> pK(+) K(-)p and pp -> pK(+)pi(0)Sigma(0) reactions have been studied in a unified approach using an effective Lagrangian model. It is assumed that both the K(-)p and pi(0)Sigma(0) final states originate from the decay of the Lambda(1405) that was formed in the production chain pp -> p(N*(1535). K+ Lambda(1405)). The available experimental data are well reproduced, especially the ratio of the two total cross sections, which is much less sensitive to the particular model of the entrance channel. The significant coupling of the N*(1535) to Lambda(1405)K is further evidence for large ss components in the quark wave function of the N*(1535).
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ATLAS Collaboration(Aad, G. et al), Amoros, G., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Escobar, C., et al. (2010). Readiness of the ATLAS Tile Calorimeter for LHC collisions. Eur. Phys. J. C, 70(4), 1193–1236.
Abstract: The Tile hadronic calorimeter of the ATLAS detector has undergone extensive testing in the experimental hall since its installation in late 2005. The readout, control and calibration systems have been fully operational since 2007 and the detector has successfully collected data from the LHC single beams in 2008 and first collisions in 2009. This paper gives an overview of the Tile Calorimeter performance as measured using random triggers, calibration data, data from cosmic ray muons and single beam data. The detector operation status, noise characteristics and performance of the calibration systems are presented, as well as the validation of the timing and energy calibration carried out with minimum ionising cosmic ray muons data. The calibration systems' precision is well below the design value of 1%. The determination of the global energy scale was performed with an uncertainty of 4%.
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