Search for particle–vibration coupling in 65Cu

The lifetime of the 9/2 + state of 65 Cu, at 2534 keV, has been measured by fast timing techniques, in order to establish wether such state arises from a weak coupling between a p3=2 proton and the 3 octupole vibration at 3.56 MeV in the 64 Ni core. The 65 Cu nucleus was populated by the reaction 7 Li + 64 Ni at 32 MeV, at the Horia Hu- lubei National Institute of Physics and Nuclear Engineering (NIPNE) in Bucharest, and its -decay was detected by the ROSPHERE array. The measured lifetime coresponds to a B(E3) reduced transition probability to the ground state equal to 8.89 W.u., in agreement with theoretical predictions in the weak coupling limit

Spectroscopy of odd-mass cobalt isotopes toward the N=40 subshell closure and shell-model description of spherical and deformed states

The neutron-rich cobalt isotopes up to A = 67 have been studied through multinucleon transfer reactions by bombarding a 238U target with a 460-MeV 70Zn beam. Unambiguous identification of prompt γ rays belonging to each nucleus has been achieved using coincidence relationships with the ions detected in a high-acceptance magnetic spectrometer. The new data are discussed in terms of the systematics of the cobalt isotopes and interpreted with large-scale shell-model calculations in the fpgd model space. In particular, very different shapes can be described in 67Co, at the edge of the island of inversion at N = 40, where a low-lying highly deformed band coexists with a spherical structureThis work was partially supported by the European Community FP6, Structuring the ERA Integrated Infrastructure Initiative Contract No. EURONS RII3-CT-2004-506065, by MICINN, Spain (Contract No. FPA2011-29854), by IN2P3, France (Contract No. AIC-D-2011-648), by Comunidad de Madrid, Spain (Contract No. HEPHACOS S2009-ESP-1473), and by Generalitat Valenciana, Spain (Contract No. PROMETEO/ 2010/101). A. Gadea and E. Farnea acknowledge the support of MICINN, Spain, and INFN, Italy, through the AIC-D-2011-0746 bilateral actio

Fast-timing study of the l -forbidden 12+→32+ M1 transition in Sn 129 FAST-TIMING STUDY of the l -FORBIDDEN ⋯ R. LICǎ et al.

© 2016 authors. Published by the American Physical Society.The levels in Sn129 populated from the β- decay of In129 isomers were investigated at the ISOLDE facility of CERN using the newly commissioned ISOLDE Decay Station (IDS). The lowest 12+ state and the 32+ ground state in Sn129 are expected to have configurations dominated by the neutron s12 (l=0) and d32 (l=2) single-particle states, respectively. Consequently, these states should be connected by a somewhat slow l-forbidden M1 transition. Using fast-timing spectroscopy we have measured the half-life of the 12+ 315.3-keV state, T12= 19(10) ps, which corresponds to a moderately fast M1 transition. Shell-model calculations using the CD-Bonn effective interaction, with standard effective charges and g factors, predict a 4-ns half-life for this level. We can reconcile the shell-model calculations to the measured T12 value by the renormalization of the M1 effective operator for neutron holes

Search for particle–vibration coupling in 65Cu

The lifetime of the 9/2+ state of 65Cu, at 2534 keV, has been measured by fast timing techniques, in order to establish wether such state arises from a weak coupling between a p3/2 proton and the 3− octupole vibration at 3.56 MeV in the 64Ni core. The 65Cu nucleus was populated by the reaction 7Li + 64Ni at 32 MeV, at the Horia Hulubei National Institute of Physics and Nuclear Engineering (NIPNE) in Bucharest, and its γ-decay was detected by the ROSPHERE array. The measured lifetime coresponds to a B(E3) reduced transition probability to the ground state equal to 8.89 W.u., in agreement with theoretical predictions in the weak coupling limit

Nanosecond lifetime measurements of Iπ¼9/2- intrinsic excited states and low-lying B(E1)strengths in 183Re using combined HPGe-LaBr3 coincidence spectroscopy

This paper presents precision measurements of electromagnetic decay probabilities associated with electric dipole transitions in the prolate-deformed nucleus 183Re. The nucleus of interest was formed using the fusion evaporation reaction 180Hf(7Li,4n)183Re at a beam energy of 30 MeV at the tandem accelerator at the HH-IFIN Institute, Bucharest Romania. Coincident decay gamma rays from near-yrast cascades were detected using the combined HPGe-LaBr3 detector array ROSPHERE. The time differences between cascade gamma rays were measured using the LaBr3 detectors to determine the half-lives of the two lowest lying spin-parity 9/2- states at excitation energies of 496 and 617 keV to be 5.65(5) and 2.08(3) ns respectively. The deduced E1 transition rates from these two states are discussed in terms of the K-hindrance between the low-lying structures in this prolate-deformed nucleus

Nanosecond lifetime measurements of Iπ¼9/2- intrinsic excited states and low-lying B(E1)strengths in 183Re using combined HPGe-LaBr3 coincidence spectroscopy

This paper presents precision measurements of electromagnetic decay probabilities associated with electric dipole transitions in the prolate-deformed nucleus 183Re. The nucleus of interest was formed using the fusion evaporation reaction 180Hf(7Li,4n)183Re at a beam energy of 30 MeV at the tandem accelerator at the HH-IFIN Institute, Bucharest Romania. Coincident decay gamma rays from near-yrast cascades were detected using the combined HPGe-LaBr3 detector array ROSPHERE. The time differences between cascade gamma rays were measured using the LaBr3 detectors to determine the half-lives of the two lowest lying spin-parity 9/2- states at excitation energies of 496 and 617 keV to be 5.65(5) and 2.08(3) ns respectively. The deduced E1 transition rates from these two states are discussed in terms of the K-hindrance between the low-lying structures in this prolate-deformed nucleus

Shape transitions far from stability: The nucleus 58Cr

AbstractExcited states up to Iπ=8+ in the neutron-rich nucleus 58Cr have been identified by using a new experimental setup composed of the large acceptance magnetic spectrometer PRISMA and the highly efficient γ-detector array CLARA. Interestingly, the excitation energy sequence of the ground-state band follows the one expected by the E(5) dynamical symmetry for a nucleus at the critical point of the shape phase transition from a spherical vibrator (U(5)) to a γ-soft rotor (O(6)). For the first time, in the same physical system, large scale shell-model calculations in the full fp shell are compared to the E(5) analytical model results and to the Interacting Boson Model. The theoretical results are in excellent agreement with the present data

Spectroscopy of neutron-rich 59-63Mn isotopes

none43The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a 238U target with a beam of 70Zn at an energy of Elab=460 MeV. Prompt γ rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.noneJ.J.VALIENTE-DOBON; S.M.LENZI; S.J.FREEMAN; LUNARDI S.; J.F.SMITH; A.GOTTARDO; F.DELLA VEDOVA; E.FARNEA; A.GADEA; D.R.NAPOLI; M.AXIOTIS; S.AYDIN; D.BAZZACCO; P.G.BIZZETI; A.M.BIZZETI-SONA; G.BENZONI; D.BUCURESCU; L.CORRADI; A.N.DEACON; G.DE ANGELIS; E.FIORETTO; B.GUIOT; M.IONESCU-BUJOR; A.IORDACHESCU; S.LEONI; N.MARGINEAN; R.MARGINEAN; P.MASON; R.MENEGAZZO; D.MENGONI; B.MILLION; G.MONTAGNOLI; R.ORLANDI; F.RECCHIA; E.SAHIN; F.SCARLASSARA; R.P.SINGH; A.M.STEFANINI; D.STEPPENBECK; S.SZILNER; C.A.UR; B.J.VARLEY; O.WIELANDJ. J., VALIENTE DOBON; Lenzi, SILVIA MONICA; S. J., Freeman; Lunardi, Santo; J. F., Smith; Gottardo, Andrea; F., DELLA VEDOVA; E., Farnea; A., Gadea; D. R., Napoli; M., Axiotis; S., Aydin; D., Bazzacco; P. G., Bizzeti; A. M., BIZZETI SONA; G., Benzoni; D., Bucurescu; L., Corradi; A. N., Deacon; G., DE ANGELIS; E., Fioretto; B., Guiot; M., IONESCU BUJOR; A., Iordachescu; S., Leoni; N., Marginean; R., Marginean; P., Mason; R., Menegazzo; Mengoni, Daniele; B., Million; Montagnoli, Giovanna; R., Orlandi; Recchia, Francesco; E., Sahin; Scarlassara, Fernando; R. P., Singh; A. M., Stefanini; D., Steppenbeck; S., Szilner; C. A., Ur; B. J., Varley; O., Wielan