RT Journal Article T1 The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus Sb-133 A1 Fraile Prieto, Luis Mario A1 Mach, H. A1 Olaizola, B. A1 Paziy, V. A1 Vedia Fernández, María Victoria AB The gamma-ray decay of excited states of the one-valence-proton nucleus Sb-133 has been studied using cold-neutron induced fission of U-235 and Pu-241 targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between gamma-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 mu s isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, revealed a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus Sn-132 and the valence proton, using Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license. PB Elsevier science SN 0370-2693 YR 2016 FD 2016-09-10 LK https://hdl.handle.net/20.500.14352/18988 UL https://hdl.handle.net/20.500.14352/18988 LA eng NO © 2016 The Authors. Published by Elsevier B.V.Artículo publicado por más de 10 autores.The authors thank the technical services of the ILL, LPSC and GANIL for supporting the EXILL campaign. The EXOGAM collaboration and the INFN Legnaro are acknowledged for the loan of Ge detectors. This work was supported by the Italian Istituto Nazionale di Fisica Nucleare, by the Polish National Science Centre under Contract Nos. 2014/14/M/ST2/00738 and 2013/08/M/ST2/00257, by the UK Science and Technology Facilities Council and the UK National Measurement Office. Supports from the German BMBF (contract No. 05P12RDNUP), the Spanish MINECO FPA2013-41267-P and NuPNET-FATIMA (PRI-PIMNUP-2011-1338) are also acknowledged. NO Ministerio de Economía y Competitividad (MINECO) NO Italian Istituto Nazionale di Fisica Nucleare NO Polish National Science Centre NO UK Science and Technology Facilities Council NO UK National Measurement Office NO German BMBF NO NuPNET-FATIMA DS Docta Complutense RD 8 abr 2025