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n_TOF Collaboration(Barbagallo, M. et al), Domingo-Pardo, C., Giubrone, G., & Tain, J. L. (2013). High-accuracy determination of the neutron flux at n_TOF. Eur. Phys. J. A, 49(12), 156–11pp.
Abstract: The neutron flux of the nTOF facility at CERN was measured, after installation of the new spallation target, with four different systems based on three neutron-converting reactions, which represent accepted cross sections standards in different energy regions. A careful comparison and combination of the different measurements allowed us to reach an unprecedented accuracy on the energy dependence of the neutron flux in the very wide range (thermal to 1 GeV) that characterizes the nTOF neutron beam. This is a pre-requisite for the high accuracy of cross section measurements at n_TOF. An unexpected anomaly in the neutron-induced fission cross section of U-235 is observed in the energy region between 10 and 30keV, hinting at a possible overestimation of this important cross section, well above currently assigned uncertainties.
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Ramos, A., Tolos, L., Molina, R., & Oset, E. (2013). The width of the omega meson in the nuclear medium. Eur. Phys. J. A, 49(11), 148–16pp.
Abstract: We evaluate the width of the omega meson in nuclear matter. We consider the free decay mode of the omega into three pions, which is dominated by rho IEuro decay, and replace the rho and pi propagators by their medium-modified ones. We also take into account the quasielastic and inelastic processes induced by a vector-baryon interaction dominated by vector meson exchange, as well as the contributions coming from the mechanism with medium-modified K , propagators. We obtain a substantial increase of the omega width in the medium, reaching a value of 121 +/- 10 MeV at normal nuclear matter density for an omega at rest, which comes mainly from omega N -> pi pi N, omega NN -> pi NN processes associated to the dominant omega -> rho IEuro decay mode. The value of the width increases moderately with momentum, reaching values of around 200MeV at 600MeV/c.
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Xiao, C. W., & Oset, E. (2013). Hidden beauty baryon states in the local hidden gauge approach with heavy quark spin symmetry. Eur. Phys. J. A, 49(11), 139–12pp.
Abstract: Using a coupled-channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-baryon interaction with hidden beauty and obtain several new states of N around 11 GeV. We consider the basis of states eta (b) N, I'N, BI > (b) , BI pound (b) , B (*) I > (b) , B (*) I pound (b) , B (*) I pound (b) (*) and find four basic bound states which correspond to BI pound (b) , BI pound (b) (*) , B (*) I pound (b) and B (*) I pound (b) (*) , decaying mostly into eta (b) N and I'N and with a binding energy about 50-130 MeV with respect to the thresholds of the corresponding channel. All of them have isospin I = 1/2 , and we find no bound states or resonances in I = 3/2 . The BI pound (b) state appears in J = 1/2 , the BI pound (b) (*) in J = 3/2 , the B (*) I pound (b) appears nearly degenerate in J = 1/2 , 3/2 and the B (*) I pound (b) (*) appears nearly degenerate in J = 1/2 , 3/2, 5/2. These states have a width from 2-110 MeV, with conservative estimates of uncertainties, except for the one in J = 5/2 which has zero width since it cannot decay into any of the states of the basis chosen. We make generous estimates of the uncertainties and find that within very large margins these states appear bound.
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Dai, L. R., & Oset, E. (2013). Tests on the molecular structure of f(2)(1270), f'(2) (1525) from psi(nS) and Upsilon(nS) decays. Eur. Phys. J. A, 49(10), 130–6pp.
Abstract: Based on previous studies that support the vector-vector molecular structure of the f(2)'(1270), f 2 (1525), K * 0 2 (1430), f0(1370) and f0(1710) resonances, we make predictions for the.(2S) decay into.(f) f2(1270),.(f) f 2 (1525), K* 0 (892) K * 0 2 (1430) and the radiative decay of.(1S),.(2S),.(2S) into.f2(1270),.f 2 (1525),.f0(1370),.f0(1710). Agreement with experimental data is found for three available ratios, without using free parameters, and predictions are done for other cases.
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Garcia Canal, C. A., Tarutina, T., & Vento, V. (2013). Nuclear and partonic dynamics in the EMC effect. Eur. Phys. J. A, 49(8), 105–5pp.
Abstract: It has been recently confirmed that the magnitude of the EMC effect measured in the electron deep inelastic scattering is linearly related to the short-range correlation scaling factor obtained from electron inclusive scattering. By using a x-rescaling approach we are able to understand the interplay between the quark-gluon and hadronic degrees of freedom in the discussion of the EMC effect.
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