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Any linguistic reform aimed at gender equality benefits from teacher’s capacity as spreaders, and literature has shown that Twitter can be used as an excellent channel for the dissemination of good practice in language use. In a mixed-methods study based on public data mining and semantic content analysis, we examine how teachers use gender-fair language (GIL) in their digital communications on Twitter, what GIL procedures they use and, if Spanish digitalk incorporates specific textisms for GIL. Results confirmed that teachers make a widespread use of GIL procedures, prefer the use of collective nouns as a GIL mechanism, and intentionally incorporate GIL into digitalk through specific textisms, what we have named gender-inclusive textisms (GIT). The findings indicate that teachers are at the forefront of gender-inclusive language activism in educational virtual communities, and that, although Twitter may contain messages that infringe upon individuals’ dignity, it is also a privileged space for linguistic innovations oriented towards gender equality

The discrepancy between experimental data and theoretical calculations in one-nucleon removal reactions at intermediate energies (quantified by the so-called “quenching factors”) and its dependence on the isospin asymmetry of the nuclei has been an open problem in nuclear physics for the last fifteen years. In this work, we propose an explanation for this long-standing problem, which relies on the inclusion of the process of core destruction due to its interaction with the removed nucleon. To include this effect, we extend the commonly used eikonal formalism via an effective nucleon density, and apply it to a series of nucleon knockout reactions. The effect of core destruction is found to depend strongly on the binding energy of the removed nucleon, leading to a significant reduction of the cross section for deeply bound nucleons, which reduces the isospin dependence of the “quenching factors”, making them more consistent with the trends found in transfer and (p,pN) reactions.

The discrepancy between experimental data and theoretical calculations in one-nucleon removal reactions at intermediate energies (quantified by the so-called “quenching factors”) and its dependence on the isospin asymmetry of the nuclei has been an open problem in nuclear physics for the last fifteen years. In this work, we propose an explanation for this long-standing problem, which relies on the inclusion of the process of core destruction due to its interaction with the removed nucleon. To include this effect, we extend the commonly used eikonal formalism via an effective nucleon density, and apply it to a series of nucleon knockout reactions. The effect of core destruction is found to depend strongly on the binding energy of the removed nucleon, leading to a significant reduction of the cross section for deeply bound nucleons, which reduces the isospin dependence of the “quenching factors”, making them more consistent with the trends found in transfer and (p,pN) reactions.

In this work, we present an extension of the Continuum-Discretized Coupled-Channel formalism to include the effects of absorption and excitation of the core through its interaction with the removed particle in the description of nuclear breakup reactions. This extension is performed via the inclusion of a complex energy-dependent interaction between core and removed particle and the use of a binormal basis to ensure orthogonality. The formalism is applied to neutron breakup reactions with a 12C target at 70 MeV per nucleon for the loosely-bound 11Be nucleus and the more deeply-bound 41Ca nucleus, finding a moderate reduction in the cross section for the weakly-bound case and a strong reduction for the more deeply-bound case. Possible implications for the interpretation of intermediate-energy knockout reactions are discussed.

In this work, we present an extension of the Continuum-Discretized Coupled-Channel formalism to include the effects of absorption and excitation of the core through its interaction with the removed particle in the description of nuclear breakup reactions. This extension is performed via the inclusion of a complex energy-dependent interaction between core and removed particle and the use of a binormal basis to ensure orthogonality. The formalism is applied to neutron breakup reactions with a 12C target at 70 MeV per nucleon for the loosely-bound 11Be nucleus and the more deeply-bound 41Ca nucleus, finding a moderate reduction in the cross section for the weakly-bound case and a strong reduction for the more deeply-bound case. Possible implications for the interpretation of intermediate-energy knockout reactions are discussed.

Two relevant time scales are introduced to describe the interplay of nuclear structure and nuclear reactions for exotic nuclei. The collision time represents the time dependence of the external field created by the target on the projectile. The excitation time represents the characteristic time dependence of the projectile degrees of freedom due to its internal Hamiltonian. The comparison of these two time scales indicate when approximate treatments of the reaction, such as the sudden approximation, implicit in the eikonal treatment, is applicable. An approach based on these time scales is used to describe recent experimental data as well as theoretical calculation involving Coulomb break-up, stripping reactions and (p, pN) reactions. It is suggested that the dependence of the stripping cross sections on the difference of binding energies of protons and neutrons may be associated to inadequacy of the eikonal approximation to describe the removal of strongly bound nucleons at intermediate energies

A novel method to extract the B(E1) strength of a weakly bound nucleus from experimental Coulomb dissociation data is proposed. The method makes use of continuum discretized coupled channels (CDCC) calculations, in which both nuclear and Coulomb forces are taken into account to all orders. This is a crucial advantage with respect to the standard procedure based on the Equivalent Photon Method (EPM) which does not properly take into account nuclear distortion, higher order coupling effects, or Coulomb- nuclear interference terms. The systematic and statistical uncertainties of this procedure are evaluated. The procedure is applied to the 11Be nucleus using two sets of available experimental data at different energies, for which seemingly incompatible B(E1) have been reported using the EPM. We show that the present procedure gives consistent B(E1) strengths, thus solving the aforementioned long-standing discrepancy between the two measurements.

A novel method to extract the B(E1) strength of a weakly bound nucleus from experimental Coulomb dissociation data is proposed. The method makes use of continuum discretized coupled channels (CDCC) calculations, in which both nuclear and Coulomb forces are taken into account to all orders. This is a crucial advantage with respect to the standard procedure based on the Equivalent Photon Method (EPM) which does not properly take into account nuclear distortion, higher order coupling effects, or Coulombnuclear interference terms. The systematic and statistical uncertainties of this procedure are evaluated. The procedure is applied to the 11Be nucleus using two sets of available experimental data at different energies, for which seemingly incompatible B(E1) have been reported using the EPM. We show that the present procedure gives consistent B(E1) strengths, thus solving the aforementioned long-standing discrepancy between the two measurements.

The elastic scattering of He-6 on Pb-208 has been measured at laboratory energies of 14, 16, 18 and 22 MeV. These data were analyzed using phenomenological Woods-Saxon form factors and optical model calculations. A semiclassical polarization potential was used to study the effect of the Coulomb dipole polarizability. Evidence for long range absorption, partially arising from Coulomb dipole polarizability, is reported. The energy variation of the optical potential was found to be consistent with the dispersion relations which connect the real and imaginary parts of the potential.

Quasi-elastic scattering of 6He at E_lab=27 MeV from 197Au has been measured in the angular range of 6-72 degrees in the laboratory system employing LEDA and LAMP detection systems. These data, along with previously analysed data of 6He + 208Pb at the same energy, are analyzed using Optical Model calculations. The role of Coulomb dipole polarizability has been investigated. Large imaginary diffuseness parameters are required to fit the data. This result is an evidence for long range absorption mechanisms in 6He induced reactions.

At the newly constructed postaccelerator REX-ISOLDE (Radioactive beam Experiment at ISOLDE) we have investigated reactions induced by a Li-9 beam incident on a deuterium target at an energy of 2.36 MeV/u. Most reaction channels were recorded. From one-neutron transfer the differential cross-section for the low lying Li-10 spectrum is found. The results from the other channels demonstrate the great applicability and many possibilities that REX-ISOLDE opens up.

We carry out a simple analysis of (n+3)-dimensional gravity in the context of recent work on 'large' supplementary dimensions and deduce a formula for the expected compactification radius for the n additional dimensions in the universe, as a function of the Planck and the electro-weak scales. We argue that the correspondingly modified gravitational force gives rise to effects that might be within the detection range of dedicated neutron experiments. A scattering analysis of the corresponding modified gravitational forces suggests that slow neutron scattering off atomic nuclei with null spin may provide an experimental test for these ideas.

Dipole polarizability refers to the effect of the excitation to negative parity states through the electric dipole interaction. In nuclear reactions induced by stable beams, dipole polarizability does not play a major role. For nuclei close to the drip lines where the separation energies of neutrons or protons are small, a substantial part of the dipole strength function occurs at low excitation energies. We propose to investigate this effect by measuring elastic scattering and break-up of Li-11 at energies below the Coulomb barrier.

The behaviour of the threshold anomaly for non-central potentials, which account for collective excitations in heavy-ion collisions, is investigated. It is shown that the non-central potentials should exhibit an energy dependence at energies in the vicinity of the Coulomb barrier. This energy dependence is, however, different from that of the elastic optical potential, occurring at lower energies. It if further shown that there are corrections to the traditional collective model such that, if the transition potential is expressed as the derivative of the optical potential, the corresponding deformation length will be complex and energy-dependent. Simple model calculations are presented.

A study of the elemental concentrations of sediments of the rivers Tinto and Odiel, in Huelva, Spain, has been performed using PIXE. Thirteen samples have been collected, seven in the Tinto and six in the Odiel. Concentrations of 19 elements have been determined in each of them. The analysis of the data illustrates the environmental impact of the mining and fertilizer plants in the area.

A simple model to understand the reaction mechanisms in the fusion of polarized heavy ions based on tidal symmetry, the sudden approximation and barrier penetration is presented. The model is applied to 23Na+208Pb. The effect of the ground state reorientation and the coupling to rotational states is studied. Enhancement of the sub-barrier fusion cross sections and the fusion J-moments just above the barrier are found. The polarization of the projectile affects strongly the fusion around and below the Coulomb barrier.

Using a single-particle description of 6,7Li and Woods-Saxon generated wavefunctions for 58Ni matter density distribution, the diagonal and transition densities are calculated. Folding these densities with the M3Y effective interaction, the coupling and diagonal potentials are obtained. Coupled channel calculations for 6,7Li on 58Ni at bombarding energies in a range from 12 to 74 MeV are performed. It is shown that the predictions of the coupled channel calculations are consistent with those of optical model calculations using folded potentials renormalized by a factor 0.6 in the entire range of energies.