Yazar "Ionescu-Bujor, M." seçeneğine göre listele

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    First measurement of the g factor in the chiral band: The case of the Cs-128 Isomeric state
    (American Physical Society, 2018) Grodner, E.; Srebrny, J.; Droste, Ch.; Prochniak, L.; Rohozinski, S. G.; Kowalczyk, M.; Ionescu-Bujor, M.; Ur, C. A.; Starosta, K.; Ahn, T.; Kisielinski, M.; Marchlewski, T.; Aydın, S.; Recchia, F.; Georgiev, G.; Lozeva, R.; Fiori, E.; Zielinska, M.; Chen, Q. B.; Zhang, S. Q.; Yu, L. F.; Zhao, P. W.; Meng, J.
    The g factor of the 56 ns half-life isomeric state in Cs-128 has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g = +0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in Cs-128 demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.
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    High-spin level structure of 35 S
    (American Physical Society, 2014) Aydın, Sezgin; Ionescu-Bujor, M.; Recchia, Francesco; Lenzi, Silvia M.; Bouhelal, Mouna; Bazzacco, Dino B.; Bizzeti, P. G.; Bizzeti-Sona A.M.
    The nucleus 35S has been studied by in-beam ?-ray spectroscopy using the 24Mg(14N,3p) fusion-evaporation reaction at Elab=40 MeV. A level scheme extended up to J?=17/2+ at 8023 keV and J?=13/2- at 6352 keV has been established. Lifetimes of six excited states have been determined by applying the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N=Z=20 shell gap. © 2014 American Physical Society.
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    High-spin states and lifetimes in S-33 and shell-model interpretation in the sd-fp space
    (American Physical Society, 2017) Aydın, Sezgin; Ionescu-Bujor, M.; Gavrilov, G. Tz.; Dimitrov, B. I.; Lenzi, Silvia M.; Recchia, Francesco; Tonev, Dimitar; Bouhelal, Mouna; Kavillioglu, F.; Pavlov, P.; Bazzacco, D.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; de Angelis, G.; Deloncle, I.; Farnea, E.; Gadea, A.; Gottardo, A.; Goutev, N.; Haas, F.; Huyuk, T.; Laftchiev, H.; Lunardi, S.; Marinov, Tz. K.; Mengoni, D.; Menegazzo, R.; Michelagnoli, C.; Napoli, D. R.; Petkov, P.; Sahin, E.; Singh, P. P.; Stefanova, E. A.; Ur, C. A.; Valiente-Dobon, J. J.; Yavahchova, M. S.
    The structure of the S-33 nucleus was investigated in the Mg-24(N-14, alpha p) fusion-evaporation reaction using a 40-MeV N-14 beam. The level scheme was extended up to an excitation energy of 11.7 MeV and spin 19/2+. Lifetimes of the intermediate-and high-spin states have been investigated by the Doppler shift attenuation method. Data were compared with different shell-model calculations where effective interactions involving two main shells, the sd and the fp, are used.
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    High-spin structure and intruder excitations in Cl-36
    (American Physical Society, 2012) Aydın, Sezgin; Recchia, Francesco; Ionescu-Bujor, M.; Gadea, Andrés; Lenzi, Silvia M.; Lunardi, Santo; Ur, Calin Alexandru; Bazzacco, Dino B.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; Bouhelal, M.; de Angelis, G.; Deloncle, I.; Farnea, E.; Gottardo, A.; Haas, F.; Huyuk, T.; Laftchiev, H.; Mengoni, D.; Menegazzo, R.; Michelagnoli, C.; Napoli, D. R.; Sahin, E.; Singh, P. P.; Tonev, D.; Valiente-Dobon, J. J.
    Excited states up to J(pi) = 11(-) at 10 296 keV and J(pi) = 10(+) at 10 707 keV have been populated in the odd-odd Cl-36 nucleus using the Mg-24(N-14,2p) fusion-evaporation reaction at E-lab = 31 MeV. Twenty new states and 62 new gamma transitions have been identified by employing gamma-gamma and gamma-gamma-gamma coincidences. Lifetimes have been investigated by the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell-model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N = Z = 20 shell gap.
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    Lifetime measurements and the high-spin structure of Cl-36
    (IOP PUBLISHING, 2015) Aydın, Sezgin; Ionescu-Bujor, M.; Recchia, Francesco; Gadea, Andrés; Lenzi, Silvia; Lunardi, Santo; Ur, C?lin Alexandru; Bazzacco, Dino
    High-spin states in Cl-36 were populated through the Mg-24(N-14,2p)Cl-36 reaction at E(N-14)=31 MeV. Lifetimes have been determined for fifteen states by applying the Doppler shift attenuation method. The results indicated the onset of collectivity in the high spin negative parity states. Large basis shell model calculations have been performed to understand the underlying structure of these states.
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    Lifetime measurements in the chiral-candidate doublet bands of La-130
    (American Physical Society, 2018) Ionescu-Bujor, M.; Aydın, Sezgin; Mârginean, Nicolae Marius; Costache, Cristian; Bucurescu, Dorel; Florea, Nicoleta Mihaela; Glodariu, Tudor R.; Ionescu, Alina Marinela
    The lifetimes of the excited states belonging to the chiral-candidate doublet bands built on the pi h(11/2) circle times vh(11/12)(-1) configuration in La-130 have been measured by applying the Doppler-shift attenuation method and the in-beam fast timing technique. Excited states were populated in the Sb-121(C-12, 3n) reaction at a bombarding energy of 54 MeV. The 7(+) bandhead of the yrast band was identified as an isomeric state with a lifetime of tau(7(+)) = 0.38(7) ns Similar reduced transition probabilities B(M1) and B(E2) were found for the states with the same spin in the partner bands. The results revealed an even-odd spin dependence in the B(E2) values, whereas the B (M1) values vary nearly monotonically with increasing spin. The experimental properties of the doublet bands in La-130 are compared with theoretical calculations done in the frame of the two-quasiparticles-plus-triaxial-rotor model. The static chirality is not supported by the obtained data; however, chiral vibrations cannot be excluded.