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ispartof: PHYSICS LETTERS B vol:820 status: published

An analysis technique has been developed in order to mitigate energy summing due to sequential short-lived α decays from nuclei implanted into a silicon detector. Using this technique, α-decay spectroscopy of the N=130 isotones Ra218 (Z=88) and Th220 (Z=90) has been performed. The energies of the α particles emitted in the Ra218→Rn214 and Th220→Ra216 ground-state-to-ground-state decays have been measured to be 8381(4) keV and 8818(13) keV, respectively. The half-lives of the ground states of Ra218 and Th220 have been measured to be 25.99(10) μs and 10.4(4) μs, respectively. The half-lives of the ground states of the α-decay daughters, Rn214 and Ra216, have been measured to be 259(3) ns and 161(11) ns, respectively. Fine structure in the α decay of Ra218 has been observed for the first time, populating the 695-keV 21+ state in Rn214. The fine-structure α decay has an α-particle energy of 7715(40) keV and branching ratio bα=0.123(11)%.

For certain combinations of protons and neutrons in atomic nuclei, a rise of a reflection asymmetry is expected. Experimental E3 strengths, which as a function of the neutron number peak at around N ≈ 88 and N ≈ 134, indicate enhanced octupole correlations as predicted by theory. Low-energy Coulomb excitation is a highly successful method for establishing the evolution of nuclear shapes, through the measurement of cross sections, to populate excited states that can be directly related to the static and dynamic moments of the charge distribution of the nucleus. A Coulomb excitation experiment at the ALTO facility, Orsay was performed recently to study collective properties of 146Nd and 148Sm. In particular, the strengths of the ⟨3−||E3||0+⟩ and ⟨1−||E3||4+⟩ matrix elements will provide a clear distinction between octupole vibration and rigid deformation. ispartof: Acta Physica Polonica B vol:47 issue:3 pages:923-928 status: published

©=0.65(+17-23) eb3/2, corresponds to a reduced B(E3) transition probability of 48(+25-34) W.u. This result represents an unambiguous determination of the octupole collectivity, is larger than any available theoretical prediction, and is consistent with octupole deformation. © 2016 American Physical Society. The neutron-rich nucleus Ba144 (t1/2=11.5 s) is expected to exhibit some of the strongest octupole correlations among nuclei with mass numbers A less than 200. Until now, indirect evidence for such strong correlations has been inferred from observations such as enhanced E1 transitions and interleaving positive- and negative-parity levels in the ground-state band. In this experiment, the octupole strength was measured directly by sub-barrier, multistep Coulomb excitation of a post-accelerated 650-MeV Ba144 beam on a 1.0-mg/cm2 Pb208 target. The measured value of the matrix element, 31-M(E3)01+

La función de control sobre la constitucionalidad de los partidos políticos ha tenido amplia difusión en Europa centro-oriental de la mano de la expansión de la justicia constitucional. Las condiciones históricas y jurídico-institucionales para la recepción de los modelos alemán y portugués estaban presentes a finales de los años ochenta en los países de Europa centro-oriental. No deja entonces de extrañar que, aunque con motivaciones opuestas a las que habían inspirado las democracias nacidas con la caída de dictaduras “de derecha”, tales ordenamientos habían optado en su mayoría por esta institución.

El juicio sobre los conflictos que pueden surgir entre los órganos supremos tiene la finalidad de garantizar el respeto de las competencias delineadas en la Constitución y, por tanto, el equilibrio entre poderes. Ello permite una solución jurisdiccional de las controversias jurídicas que surgen entre sujetos y órganos de relevancia constitucional, con el resultado de sustraerlas de las decisiones de órganos de naturaleza política.

La confianza a los tribunales constitucionales de la competencia en materia de disputas electorales es interpretada como la prueba de la voluntad para redimensionar el papel del Parlamento y de los partidos. Se trata de una función que tiene una doble incidencia: por una parte, entra en juego el enlace entre la voluntad popular y la representación política mediante la garantía del derecho de votar. Tal atribución se coloca en una tendencia de concebir el momento electoral como piedra angular de la democracia constitucional.