Binding-energy independence of reduced spectroscopic strengths derived from (p, 2p) and (p, pn) reactions with nitrogen and oxygen isotopes

A campaign of intermediate energy (300-450 MeV/u) proton-induced nucleon knockout measurements in inverse kinematics has been recently undertaken at the R 3 B/LAND setup at GSI. We present a systematic theoretical analysis of these data with the aim of studying the quenching of the single-particle strengths and its binding-energy dependence. For that, the measured semi-inclusive (p, 2p) and (p, pn) cross sections are compared with theoretical predictions based on single-particle cross sections derived from a novel coupled-channels formalism and shell-model spectroscopic factors. A systematic reduction of about 20-30% is found, with a very limited dependence on proton-neutron asymmetry.Comment: 8 pages, 3 figure

Description of the 11^{11}Li(p,d)10(p,d){^{10}}Li transfer reaction using structure overlaps from a full three-body model

Recent data on the differential angular distribution for the transfer reaction $^{11}$Li(p,d)$^{10}$Li at $E/A=5.7$ MeV in inverse kinematics are analysed within the DWBA reaction framework, using the overlap functions calculated within a three-body model of $^{11}$Li. The weight of the different $^{10}$Li configurations in the system's ground state is obtained from the structure calculations unambiguously. The effect of the $^{9}$Li spin in the calculated observables is also investigated. We find that, although all the considered models succeed in reproducing the shape of the data, the magnitude is very sensitive to the content of $p_{1/2}$ wave in the $^{11}$Li ground-state wave function. Among the considered models, the best agreement with the data is obtained when the $^{11}$Li ground state contains a $\sim$31\% of $p_{1/2}$ wave in the $n$-$^9$Li subsystem. Although this model takes into account explicitly the splitting of the $1^+$ and $2^+$ resonances due to the coupling of the $p_{1/2}$ wave to the $3/2^-$ spin of the core, a similar degree of agreement can be achieved with a model in which the $^{9}$Li spin is ignored, provided that it contains a similar p-wave content.Comment: 8 pages, 3 figures. Final versio

Linking structure and dynamics in (p,pn)(p,pn) reactions with Borromean nuclei: the 11^{11}Li(p,pn)10(p,pn){^{10}}Li case

One-neutron removal $(p,pn)$ reactions induced by two-neutron Borromean nuclei are studied within a Transfer-to-the-Continuum (TC) reaction framework, which incorporates the three-body character of the incident nucleus. The relative energy distribution of the residual unbound two-body subsystem, which is assumed to retain information on the structure of the original three-body projectile, is computed by evaluating the transition amplitude for different neutron-core final states in the continuum. These transition amplitudes depend on the overlaps between the original three-body ground-state wave function and the two-body continuum states populated in the reaction, thus ensuring a consistent description of the incident and final nuclei. By comparing different $^{11}$Li three-body models, it is found that the $^{11}$Li$(p,pn){^{10}}$Li relative energy spectrum is very sensitive to the position of the $p_{1/2}$ and $s_{1/2}$ states in $^{10}$Li and to the partial wave content of these configurations within the $^{11}$Li ground-state wave function. The possible presence of a low-lying $d_{5/2}$ resonance is discussed. The coupling of the single particle configurations with the non-zero spin of the $^{9}$Li core, which produces a spin-spin splitting of the states, is also studied. Among the considered models, the best agreement with the available data is obtained with a $^{11}$Li model that incorporates the actual spin of the core and contains $\sim$31\% of $p_{1/2}$-wave content in the $n$-$^9$Li subsystem, in accord with our previous findings for the $^{11}$Li(p,d)$^{10}$Li transfer reaction, and a near-threshold virtual state.Comment: 7 pages, 4 figures, submitted to PL

Investigating the 10Li continuum through 9Li(d,p)10Li reactions

The continuum structure of the unbound system $^{10}$Li, inferred from the $^{9}$Li$(d,p)^{10}$Li transfer reaction, is reexamined. Experimental data for this reaction, measured at two different energies, are analyzed with the same reaction framework and structure models. It is shown that the seemingly different features observed in the measured excitation energy spectra can be understood as due to the different incident energy and angular range covered by the two experiments. The present results support the persistence of the $N=7$ parity inversion beyond the neutron dripline as well as the splitting of the well-known low-lying $p$-wave resonance. Furthermore, they provide indirect evidence that most of the $\ell=2$ single-particle strength, including possible $d_{5/2}$ resonances, lies at relatively high excitations energies.Comment: accepted for publication in Physics Letters

New rational extensions of solvable potentials with finite bound state spectrum

Using the disconjugacy properties of the Schr\"odinger equation, it is possible to develop a new type of generalized SUSY QM partnership which allows to generate new solvable rational extensions for translationally shape invariant potentials having a finite bound state spectrum. For this we prolong the dispersion relation relating the energy to the quantum number out of the physical domain until a disconjugacy sector. The prolonged excited states Riccati-Schr\"odinger (RS) functions are used to build Darboux-B\"acklund transforms which give regular isospectral extensions of the initial potential. We give the spectra of these extensions in terms of new orthogonal polynomials and study their shape invariance properties

Actualidad de la Hermenéutica

Sin resume

La paradoja de la estupidez

Este ensayo explora la relación entre el fenómeno de la estupidez y la construcción de la subjetividad en el proceso formativo de la educación. A partir de la lectura de dos ensayos clásicos sobre la estupidez, el de Robert Musil y el de Eduard Erdmann, se establece el carácter paradójico de la estupidez. Por un lado equivale a la incapacidad para adoptar puntos de vista distintos del propio, y, en esa medida, puede ser corregida por el proceso de la Bildung, de la adquisición de la facultad de juzgar y, con ello, de la formación de una subjetividad propia. El Juicio, sobre todo, que requiere precisamente de esos puntos de vista ajenos, tal como se muestra, con notables implicaciones políticas y críticas, en la obra de Hannah Arendt y en la tercera crítica de Kant. Por otro lado, la estupidez es un concepto práctico de las relaciones intersubjetivas que responde a la opacidad de las conductas ajenas; pero, también, y sobre todo, la estupidez da cuenta del núcleo más íntimo e irreductible de cada subjetividad: aquel que no puede ser recogido por ningún juicio. La estupidez tiene así una relación paradójica en la constitución de los sujetos, y a esa paradoja debe atender la educación.This essay explores the connection between the stupidity phenomenon and the subjectivity construction in the educational formation process. From the reading of two classical essays about the stupidity, written by Robert Musil and Eduard Erdmann, is established the paradox character of the stupidity. On one hand, it is equivalent to the incapacity of adopting different points of view about itself, and, in what regards it, may be corrected by the process of the Bildung, that is the acquisition of the judgment faculty and, from that, the capacity of building an own subjectivity. This judgment, specially, requires these points of view from the outside as it appears, with notable political and critical implications in Hannah Arendt’s work and in Kant’s third Critic. On the other hand, the stupidity is a practical concept of the intersubjective relations that correspond to the opacity of the others conduct, but also, and specially, the stupidity concerns about the inner and irreducible circle of each subjectivity: that one that can’t be covered by any judgment. Thus, the stupidity has a paradoxical relation in the subject constitution and this paradox must attend the education.Este trabajo se desarrolla en el marco del proyecto de investigación “Encrucijadas de la subjetividad: experiencia, memoria e imaginación” (FFI2012-32033), financiado por el MEC del gobierno de España

Prevalencia de hábitos de vida saludables en estudiantes universitarios

La población universitaria es más vulnerable a no adoptar unos hábitos de vida saludable, debido a los cambios en su vida diaria con el comienzo de la etapa universitaria. Se ha observado que existe una alta prevalencia de obesidad en este grupo debido a una alimentación inadecuada y a la falta de actividad física. También influyen otros factores que les propician a seguir unos hábitos tóxicos como el consumo de alcohol y tabaco, relaciones sexuales sin protección o la falta de sueño. Por ello se plantea la realización de un estudio observacional, descriptivo y transversal, en el que se utilizarán cuestionarios y test validados para la evaluación de cada conducta, con el objetivo de conocer y describir los hábitos de vida de la población universitaria, y su interrelación. Se plantea que el estudio sea llevado a cabo en la Universidad de Valladolid con estudiantes de entre 18 y 24 años. Para fomentar la participación se les dará una papeleta para el sorteo de unas entradas para un concierto. Será totalmente anónimo y se recogerán datos sociodemográficos, información dietética (recordatorio de consumo de alimentos de 24 horas), información sobre la actividad física (test IPAQ), información sobre el consumo de tabaco (test Fagerström y test Richmond), información sobre el consumo de alcohol (test AUDIT), información sobre la sexualidad e información sobre el sueño (test de Pittsburg).Grado en Enfermerí