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The competition among reaction processes of a weakly-bound projectile at intermediate times of a slow collision has been unravelled. This has been done using a two-center molecular continuum within a semiclassical, time-dependent coupled-channel reaction model. Dynamical probabilities of elastic scattering, transfer and breakup agree with those derived from the direct integration of the time-dependent Schrodinger equation, demonstrating the usefulness of a two-center molecular continuum for gaining insights into the reaction dynamics of exotic nuclei.

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Background: The problem of the scattering of a one-neutron halo nucleus by another nucleus might involve an extremely complicated solution, particularly when breakup and rearrangement channels are to be considered. Purpose: We construct a simple model to study the evolution of a single-particle wave function during the collision of a one-dimensional potential well by another well. Method: Our one-dimensional model provides the essential three-body nature of this problem, and allows for a much simpler application and assessment of different methods of solution. To simplify further the problem, we assume that the potential well representing the projectile moves according to a predetermined classical trajectory, although the internal motion of the “valence” particle is treated fully quantum mechanically. This corresponds to a semiclassical approach of the scattering problem, applicable in the case of heavy projectile and target. Different approaches are investigated to understand the dynamics involving one-body halo-like systems: the “exact” time-dependent solution of the Schrödinger equation is compared to a numerical continuum-discretized coupled-channels (CC) calculation presenting various model cases including different reaction channels. Results: This framework allows us to discuss the reaction mechanism and the role of the continuum, the inclusion of which in the CC calculation results to be crucial to reproduce the exact solution, even when the initial and final states are well bound. Conclusions: The dynamical situations under study can be linked to analogous problems solved in a threedimensional (3D) CC framework, so the present model provides a simple tool to understand the main challenges experienced in the usual 3D models with the treatment of the continuum United Kingdom Science and Technology Facilities Council (STFC) ST/L005743/1.

Background: Aside from being a one-neutron halo nucleus, $^{15}\mathrm{C}$ is interesting because it is involved in reactions of relevance for several nucleosynthesis scenarios.Purpose: The aim of this work is to analyze various reactions involving $^{15}\mathrm{C}$, using a single structure model based on halo effective field theory (halo EFT) following the excellent results obtained in [P. Capel et al., Phys. Rev. C 98, 034610 (2018)].Method: To develop a halo-EFT model of $^{15}\mathrm{C}$ at next to leading order (NLO), we first extract the asymptotic normalization coefficient (ANC) of its ground state by analyzing $^{14}\mathrm{C}(d,p)^{15}\mathrm{C}$ transfer data at low energy using the method developed in [J. Yang and P. Capel, Phys. Rev. C 98, 054602 (2018)]. Using the halo-EFT description of $^{15}\mathrm{C}$ constrained with this ANC, we study the $^{15}\mathrm{C}$ Coulomb breakup at high (605 MeV/nucleon) and intermediate (68 MeV/nucleon) energies using eikonal-based models with a consistent treatment of nuclear and Coulomb interactions at all orders, and which take into account proper relativistic corrections. Finally, we study the $^{14}\mathrm{C}(n,\ensuremath{\gamma})^{15}\mathrm{C}$ radiative capture.Results: Our theoretical cross sections are in good agreement with experimental data for all reactions, thereby assessing the robustness of the halo-EFT model of this nucleus. Since a simple NLO description is enough to reproduce all data, the only nuclear-structure observables that matter are the $^{15}\mathrm{C}$ binding energy and its ANC, showing that all the reactions considered are purely peripheral. In particular, it confirms the value we have obtained for the ANC of the $^{15}\mathrm{C}$ ground state: ${\mathcal{C}}_{1/{2}^{+}}^{2}=1.59\ifmmode\pm\else\textpm\fi{}0.06\phantom{\rule{4pt}{0ex}}{\mathrm{fm}}^{\ensuremath{-}1}$. Our model of $^{15}\mathrm{C}$ provides also a new estimate of the radiative-capture cross section at astrophysical energy: ${\ensuremath{\sigma}}_{n,\ensuremath{\gamma}}(23.3\phantom{\rule{0.16em}{0ex}}\mathrm{keV})=4.66\ifmmode\pm\else\textpm\fi{}0.14\phantom{\rule{0.16em}{0ex}}\ensuremath{\mu}\mathrm{b}$.Conclusions: Including a halo-EFT description of $^{15}\mathrm{C}$ within precise models of reactions is confirmed to be an excellent way to relate the reaction cross sections and the structure of the nucleus. Its systematic expansion enables us to establish how the reaction process is affected by that structure and deduce which nuclear-structure observables are actually probed in the collision. From this, we can infer valuable information on both the structure of $^{15}\mathrm{C}$ and its synthesis through the $^{14}\mathrm{C}(n,\ensuremath{\gamma})^{15}\mathrm{C}$ radiative capture at astrophysical energies.

We analyze the breakup of the one-neutron halo nucleus 11Be measured at 520 MeV/nucleon at GSI on Pb and C targets within an eikonal description of the reaction including a proper treatment of special relativity. The Coulomb term of the projectile-target interaction is corrected at first order, while its nuclear part is described at the optical limit approximation. Good agreement with the data is obtained using a description of 11Be, which fits the breakup data of RIKEN. This solves the apparent discrepancy between the dB(E1)/dE estimations from GSI and RIKEN for this nucleus., SCOPUS: ar.j, info:eu-repo/semantics/published

In this note we illustrate some applications of a simple model which has been devised to clarify the reaction mechanism and the interplay of different reaction channels (elastic, inelastic, transfer, break-up) in heavy-ion collisions. The model involves two potential wells moving in one dimension and few active particles; in spite of its simplicity, it is supposed to maintain the main features, the properties and the physics of the full three-dimensional case. Special attention is given to the role of continuum states in reactions involving weakly-bound systems, and different approximation schemes (as first-order or coupled-channels) as well as different continuum discretization procedures are tested. In the case of two active particles the reaction mechanism associated with two-particle transfer and the effect of pairing intearction are investigated., SCOPUS: cp.p, info:eu-repo/semantics/published

TNPI2016 : XV Conference on Theoretical Nuclear Physics in Italy A line of research has been developed to describe structure and dynamics of weakly-bound systems with one or more valence particles. To simplify the problem we are assuming particles moving in one dimension and, despite the drastic assumption, the model encompasses many characteristics observed in experiments. Within this model we can describe, for example, one- and two-particle breakup and one- and two-particle transfer processes. We concentrate here in models involving weakly-bound nuclei with just one valence particle. Exact solutions obtained by directly solving the time-dependent Schroedinger equation can be compared with the results obtained with different approximation schemes (coupled-channels formalism, continuum discretization, etc). Our goal is to investigate the limitations of the models based on approximations, and in particular to understand the role of continuum in the reaction mechanism.

Charlotte Perkins Gilman anticipated Amartya Sen's theories on the economy of wellbeing and the theory of the capabilities by placing humanity at the centre of economic politics, the full development of abilities of the entire population and the participation in all the social, economic and political activities of men and women, as a premise for social progress and genuine democracy. In particular, she highlighted the value of women's competences and female innovative contribution towards the achievement of these goals. Today, the European Union considers these issues as a priority but in Italy they are not fully taken into consideration. Gilman, the American authoritative sociologist and economist, defined in 1993 by the Women's Hall of Fame as one of the 10 most influential women of the twentieth century, thanks to her studies and her in-depth analysis of women's real conditions of life, reached the conclusion that the origins of the traditional sexual roles – and of the female ‘natural’ subordination t...

A line of research has been developed to describe the structure and the dynamics of weakly-bound systems with one or more valence particles. To simplify the problem we are assuming particles moving in one dimension. Within this model one can describe, for example, direct reactions involving one or two valence neutrons: inelastic scattering, breakup and transfer processes. Exact solutions obtained by directly solving the many-body time-dependent Schrodinger equation can be compared with the results obtained with different approximate schemes (first-order, coupled channels, continuum discretization, etc.). In this contribution we concentrate on inelastic scattering.

A line of research has been developed to describe the structure and the dynamics of weakly-bound systems with one or more valence particles. To simplify the problem we are assuming particles moving in one dimension. Within this model one can describe, for example, one- and two-particle break-up and one- and two-particle transfer processes. In the case of reactions involving two particles one can study in particular the proper reaction mechanism in connection with the role of the pairing interaction. Exact solutions obtained by directly solving the many-body time-dependent Schroedinger equation can be compared with the results obtained with different approximation schemes (first-order, coupled channels, continuum discretization, etc). In this particular contribution we concentrate on one-particle transfer processes.

We discuss the reaction mechanism associated with two-particle transfer reactions in a simple one-dimensional model. The reaction process is generated by two colliding wells and we follow in time the evolution of the two-particle wave function, initially concentrated in one of the two wells. At the end of the process one can single out the population of the different final channels, including one and two-particle transfer. When a residual short-ranged pairing interaction among the two particles is included in addition to the moving potentials, one observes a clear enhancement of the pair transfer as compared to the expectation of a pure sequential one-particle transfers. The final “exact” solution can be compared to the one obtained within different reaction and structure models (as coupled-channels, first-order approximation, approximate treatment of the continuum, etc), so providing important information on the reaction mechanism associated with the different processes.

22 págs.; 13 figs.; 1 tab.; 1 app., We construct a one-dimensional toy model to describe the main features of Borromean nuclei at the continuum threshold. The model consists of a core and two valence neutrons, unbound in the mean potential, that are bound by a residual point contact density-dependent interaction. Different discretization procedures are used (harmonic oscillator and transformed harmonic oscillator bases, or use of large rigid wall box). Resulting energies and wave functions, as well as inelastic transition intensities, are compared within the different discretization techniques, as well as with the exact results in the case of one particle and with the results of the di-neutron cluster model in the two particles case. Despite its simplicity, this model includes the main physical features of the structure of Borromean nuclei in an intuitive and computationally affordable framework, and will be extended to direct reaction calculations. © 2016 IOP Publishing Ltd Printed in the UK, Part of this work was funded by MINECO grant FIS2014-53448-C2-2-P. LM thanks the University of Huelva, where part of this work was done with the finantial support of the Erasmus Placement program.

A simple 1D toy model to study one-neutron transfer reactions is developed. It is based on the solution of the time dependent Schroedinger equation for a particle initially bound by a fixed potential well, perturbed by a second moving potential, which accounts for the second partner of the reaction. At the end of the time evolution it is possible to evaluate the probability of the transfer of the particle from a potential to the other, as well as the transfer to continuum states in the case of weakly-bound systems. Although rather simple, the model accounts for most of the physical characteristics of these kind of reactions: such as the existence of an optimum Q-value and the dependence on the parameters defining the relative motion of the two potentials.

In this work we study one-neutron halo nuclei, and in particular 11Be and 15C, which can be seen as an inert core of 10Be or 14C plus a loosely bound neutron. During the last decades several transfer and breakup reactions involving these systems have been measured on different targets and energies. We study these processes using one single structure model for each nucleus applying the halo effective field theory (Halo EFT) at next-to-leading order NLO. The main parameters of this EFT are adjusted on nuclear-structure data and/or ab initio predictions. We model the transfer reaction within the Adiabatic Distorted Wave Approximation (ADWA) and the breakup process applying an eikonal model with a consistent treatment of nuclear and Coulomb interactions at all orders. At high energy, our model includes a proper treatment of special relativity Our theoretical calculations are in good agreement with experiment for a variety of reaction observables, thus assessing the robustness of the structure model provided for these nuclei. This new idea enables us also to reliably estimate the nuclear-structure observables that actually affect the reaction process, and hence that can be inferred from such measurements.

Il volume raccoglie interventi di studiose di diverse discipline su personaggi femminili che abbiano o abbiano avuto un ruolo sociale e culturale di rilievo, in prospettiva internazionale e plurilinguistica. Women on Women intende mostrare la necessità e al contempo il superamento della prospettiva di alcune accezioni degli studi di genere, che restituiscono l’idea di “appannaggio femminile”. Lo studio del pensiero delle donne nelle diverse aree prese in considerazione non si pone invece come studio del femminile, ma come dimostrazione della presenza delle donne nel pensiero disciplinare, e quindi dell’opportunità di reintegrarne l’azione nel canone disciplinare. La ricerca che ha sostenuto l’indagine investe donne più e meno conosciute in diversi continenti (Europa occidentale, Europa orientale, Stati Uniti) tra il XVIII e il XXI secolo. Il progetto non si inserisce in una tradizione “femminista”, ma vuole dimostrare la necessità di una scoperta congiunta che favorisca la costruzione di un’identità olistica dell’individuo sociale. Donne non solo per le donne, con le donne, alle donne. Donne e uomini per la formazione e il progresso del sé e della società attraverso la cultura.

Si parla molto di giovani, di materie scientifiche, umanistiche del primato delle une o delle altre, del disinteresse dei giovani per un tipo o l'altro di studio e di professioni, dei valori, dei desideri...ma chi interroga i/le giovani? per questo la ricerca ha chiesto a loro il loro parere e le conclusioni sono riflessioni sul senso del nostro sistema e sul fatto che occorre una rivoluzione "gentile" proprio come vorrebbero i/le giovani.

I media costituiscono ormai un potente strumento formativo. Accompagnano la formazione dalle primissime fasi della vita condizionando spesso le scelte di vita, di studio e l'ingresso e alla permanenza nel mondo del lavoro attraverso gli stereotipi. Per questo è necessario conoscerli ed individuarli per neutralizzarli. Questo volume è frutto delle tesi finali del Master in Formatori ed esperti in Pari Opportunità, Università Roma Tre

La maternità è stata oggetto di molte mitizzazioni. Dalla Dea madre al culto vittoriano della madre, la maternità è passata da una fondamentale funzione sociale ad essere un "problema" che genera ingiustizie e disuguaglianze, oltreché non consente la piena cittadinanza femminile. Questo saggio è un'analisi dei miti e delle realtà sulla maternità.

Gli stereotipi passano spesso inosservati e agiscono in questo modo molto più efficacemente. Tra le righe dei testi o nelle parole e immagini dei media si nascondono i modelli in base ai quali inconsapevolmente siamo formati.

Le pari opportunità sono uno strumento di democrazia e come tale devono essere apprese durante il corso della formazione del cittadino e della cittadina in un'ottica di convivenza civile e rispettosa di se stessi come degli altri membri della società. Per questo motivo è importante che l'argomento venga trattato a scuola. A questo fine il personale docente stesso deve essere formato.