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AbstractAbstract

[en] Excitation functions for

^{169}Tm (α, χn),^{181}Ta (α, χn) and^{209}Bi (α, χn) up to 70 MeV using the stacked foil activation technique and high-resolution Ge(Li) gamma-ray spectroscopy method. The experimental results were compared with calculations considering the equilibrium as well as pre-equilibrium hybrid model of Blann (ALICE/90). A general agreement was found for all reactions with initial exciton configuration n_{O}=4(4pOh) at high energyPrimary Subject

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Journal Article

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Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1439-1452

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AbstractAbstract

[en] Power corrections both to the strong coupling constant and to the structure function itself are estimated on the basis of the LO, NLO and NNLO QCD analysis of x

_{F}3 structure function data. The sign of the correction to the coupling constant is found to be negative. The x-shape of a higher twist contribution to the structure function is stable up to NNLOPrimary Subject

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Journal Article

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Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1527-1530

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AbstractAbstract

[en] The radiation damage induced by 27 MeV protons has been studied on diodes fabricated from standard and oxygen-enriched FZ substrates. Measurements confirm that the damage constant α is insensitive to the oxygen concentration whereas the acceptor creation rate parameter β is lower for oxygenated diodes. However, the effect is significantly smaller than that observed with high-energy protons, but some what higher than that by reactor neutrons. Data have been collected at the irradiation facility of the tandem at the INFN (National Institute of Nuclear Physics) laboratory of Legnaro (Italy)

Primary Subject

Source

4. International conference on large scale applications radiation hardness of semiconductor detectors; Florence (Italy); 23-25 Jun 1999

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Journal Article

Literature Type

Conference

Journal

Nuovo Cimento. A; CODEN NCIAAT; v. 112A(11); p. 1377-1382

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AbstractAbstract

[en] In the present work, the binding energy, pressure, incompressibility, the density and effective mass of nucleon and delta isobar in the relativistic Δ-resonance nuclear matter at finite temperature are studied in the relativistic δ-ω-π model. The one-loop vacuum fluctuation of nucleon and the Δ-isobar is very important to the properties of Δ-resonance nuclear matter, even if at low temperature. The pressure density calculated both in quantum hadrodynamics model and in thermostatistical mechanics is consistent. The density of nucleon ( Δ-isobar) decreases (increases), respectively, for a given baryon density, when temperature increases

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Journal Article

Journal

Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1509-1518

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AbstractAbstract

[en] A 3D form (under the covariant instantaneous Ansatz) of the Bethe-Salpeter equation (BSE) with a Lorentz-invariant, spin-dependent confining kernel is made use of to study the low-lying gg states and derive their spectrum. The sensitivity of the gluonium spectrum to m

_{g}, the free parameter used in this model, is studied. Comparison of predictions of some gg states is done with these of other models and some experimental candidatesPrimary Subject

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Journal Article

Journal

Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1531-1540

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AbstractAbstract

[en] Spontaneous symmetry breaking and the Weinberg-Salam model have been reformulated in terms of quaternion-valued field variables. The quaternion-valued scalar Lagrangian reduces to four different field equations associated with the scalar quartet of a quaternion field φ φ

_{0}+e_{1φ1}+e_{2φ2}+e_{3φ3}. It has been shown that the quaternion gauge group SO(4) is spontaneously broken to two gauge groups of SU(2) non Abelian gauge fields. The Weinberg-Salam model of electroweak interaction has been extensively studied to enlarge the gauge group structure SU(2)_{L}xSU(2)_{R}xU(1)Primary Subject

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Journal Article

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Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1583-1591

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AbstractAbstract

[en] Muon capture on N≠Z nuclei is discussed within an algebraic approach in the frame of the version 3 of the interacting boson model (IBM) of nuclear structure, thus including the isospin degree of freedom. A simple formula for the capture rate is worked out and compared with experimental data. Inclusive measurements are suggested in order to verify the validity of an IBM-4 supersymmetry scheme for the sd-shell nuclei

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Journal Article

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Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1489-1499

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AbstractAbstract

[en] The purpose of this paper is to present a unified derivation for obtaining all of these conserved quantities based on their relationship to the group of conformal transformations. In addition to including the well-known demonstration that the inhomogeneous Lorentz group of transformations leads to the conserved energy-momentum vector and to the conserved angular momentum-Lorentz momentum tensor, this work shows that the dilation transformation leads directly to the conserved dilation scalar without scaling of the mass, which was required in the original derivation, and that the acceleration transformation yields the conserved conformal vector, which was previously obtained without explicit use of the acceleration transformation

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Journal Article

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Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1553-1569

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[en] The energy spectrum of the diffuse radiation arising from the decay products of antiprotons has been calculated in the baryon symmetric universe over 6 decades in energy, from the x-ray to the gamma-ray region. All the 10 decades modes considered in this investigation give rise to a spectral peak in the X-ray region. In addition to this, 7 of them show a strong enhancement of the flux above 100MeV and a cut-off around 450 MeV. However, the observed diffuse radiation has a smooth spectrum without any feature and hence lower limits to the partial lifetime of antiprotons have been derived for the 10 decay modes. The higher limit derived here is about 15 orders of magnitude better than those obtained from direct measurements

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Journal Article

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Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1593-1605

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AbstractAbstract

[en] The paper presents a few simple observations on the occurrence of π-condensation in nuclei, aimed at clarifying the nature of the π-condensation implied by the coherent nuclear π-Ν-Δ interaction, proposed in 1990 to explain the puzzling emergence of the shell-model. This condensation is totally unrelated to the one proposed by A.N. Migdal at the beginning of the 70s, which can easily be shown not to occur at the normal nucleon density ρ

_{Ν}asymptotically equal to 0.17 fm^{-3}Primary Subject

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Journal Article

Journal

Nuovo Cimento. A; CODEN NCIAAT; v. 112A(12); p. 1609-1614

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