0000000000412047
AUTHOR
Martín Alcorta
showing 6 related works from this author
Fission Barrier of Superheavy Nuclei and Persistence of Shell Effects at High Spin: Cases ofNo254andTh220
2014
We report on the first measurement of the fission barrier height in a heavy shell-stabilized nucleus. The fission barrier height of No-254 is measured to be B-f = 6.0 +/- 0.5 MeV at spin 15 (h) over bar and, by extrapolation, B-f = 6.6 +/- 0.9 MeV at spin 0 (h) over bar. This information is deduced from the measured distribution of entry points in the excitation energy versus spin plane. The same measurement is performed for Th-220 and only a lower limit of the fission barrier height can be determined: B-f (I) > 8 MeV. Comparisons with theoretical fission barriers test theories that predict properties of superheavy elements.
Exploring the stability of super heavy elements: First Measurement of the Fission Barrier of $^{254} $No
2013
The gamma-ray multiplicity and total energy emitted by the heavy nucleus 254No have been measured at 2 different beam energies. From these measurements, the initial distributions of spin I and excitation energy E * of 254No were constructed. The distributions display a saturation in excitation energy, which allows a direct determination of the fission barrier. 254No is the heaviest shell-stabilized nucleus with a measured fission barrier. © Owned by the authors, published by EDP Sciences, 2014.
The β-decay approach for studying 12C
2008
6 pags., 3 figs. -- 9th International Conference on Clustering Aspects of Nuclear Structure and Dynamics (CLUSTERS'07) 3–7 September 2007, Stratford upon Avon, UK
Precise branching ratios to unbound 12C states from 12N and 12B β-decays
2009
6 pages, 2 tables, 4 figures.--PACS nrs.: 21.45.-v; 23.40.-s; 27.20.+n; 21.60.De.--Printed version published Aug 3, 2009
Stability and synthesis of superheavy elements: Fighting the battle against fission – example of $^{254}$No
2016
International audience; Superheavy nuclei exist solely due to quantum shell effects,which create a pocket in the potential-energy surface of the nucleus, thusproviding a barrier against spontaneous fission. Determining the height ofthe fission barrier and its angular-momentum dependence is important toquantify the role that microscopic shell corrections play in enhancing andextending the limits of nuclear stability. In this talk, the first measurement ofa fission barrier in the very heavy nucleus 254No will be presented.
Decay and Fission Hindrance of Two- and Four-QuasiparticleKIsomers inRf254
2015
Two isomers decaying by electromagnetic transitions with half-lives of 4.7(1.1) and 247(73) μs have been discovered in the heavy ^{254}Rf nucleus. The observation of the shorter-lived isomer was made possible by a novel application of a digital data acquisition system. The isomers were interpreted as the K^{π}=8^{-}, ν^{2}(7/2^{+}[624],9/2^{-}[734]) two-quasineutron and the K^{π}=16^{+}, 8^{-}ν^{2}(7/2^{+}[624],9/2^{-}[734])⊗8^{-}π^{2}(7/2^{-}[514],9/2^{+}[624]) four-quasiparticle configurations, respectively. Surprisingly, the lifetime of the two-quasiparticle isomer is more than 4 orders of magnitude shorter than what has been observed for analogous isomers in the lighter N=150 isotones. …