Lifetime measurements of short-lived excited states, and shape changes in As 69 and Ge 66 nuclei

Basit Öğe Kaydı
dc.authorid0000-0002-1142-8067
dc.contributor.authorMatejska Minda, M.
dc.contributor.authorBednarczyk, Piotr
dc.contributor.authorFornal, Bogdan
dc.contributor.authorXu, Furong
dc.contributor.authorLiang, Wuyang
dc.contributor.authorde Angelis, Giacomo
dc.contributor.authorAydın, Sezgin
dc.date.accessioned2020-02-13T08:30:50Z
dc.date.available2020-02-13T08:30:50Z
dc.date.issued2019
dc.departmentSabire Yazıcı Fen Edebiyat Fakültesi
dc.descriptionAydın, Sezgin ( Aksaray, Yazar )
dc.description.abstractBackground: The nuclear shape is a macroscopic feature of an atomic nucleus that is sensitive to the underlying nuclear structure in terms of collectivity and the interaction between nucleons. Therefore, the evolution of nuclear shapes has attracted many theoretical and experimental nuclear structure studies. The structure of the A?70, N?Z nuclei, lying far from the stability line, is interesting because a particularly strong proton-neutron correlation may occur here due to the occupation of the same orbits by nucleons of both types. In this region, different particle configurations drive a nucleus towards various deformed shapes: prolate, oblate, octupole, or nonaxial. These nuclear shapes change rapidly with nucleon number and also with angular momentum. This is reflected by a presence of different structures (bands) of excited states which exhibit a broad range of lifetimes. Purpose: The aim of this paper is to determine lifetimes of some high-spin excited states in As69 and Ge66 nuclei to examine the shape evolution in these neutron-deficient nuclei. Methods: Lifetimes of high-spin states in As69 and Ge66 have been measured by using the Doppler-shift attenuation technique with the GASP and recoil filter detector setup at the Laboratori Nazionali di Legnaro. The nuclei of interest were produced in the S32(95MeV)+0.8mg/cm2 Ca40 fusion-evaporation reaction. The strongest reaction channels 3p and ?2p led to the As69 and Ge66 final nuclei, respectively. Using ?-?-recoil coincidences we were able to determine very short lifetimes (in the femtosecond range) in the residual nuclei of interest. Results: In As69, the extracted lifetimes are ?=72 (-32, +45) fs for the 33/2+ state at 7897 keV and ?<85 fs for the 37/2+ state at 9820 keV. For the Ge66 case, the lifetime of the 11- state at 7130 keV is ?=122(±41) fs. Lifetimes in As69 and Ge66 reported in this paper have been measured for the first time in the present experiment. Conclusions: The results are discussed in the terms of deformation and shape evolution in As69 and Ge66. The quadrupole moments deduced from the measured lifetimes were compared with the cranked Woods-Saxon-Strutinsky calculations by means of the total Routhian surface method. It turns out that Band 3 in As69 shows an oblate-prolate shape transition, and above spin 33/2+ it corresponds to a prolate collective structure with ?2?0.27 and ??20. In turn, in Ge66 the negative-parity band built on the 7- state at 4205 keV corresponds to a triaxial shape with ?2=0.33 and ?=31. Analysis of the transitional quadrupole moments derived from the experimental and theoretical ones points to a significant change of deformation in the As69 and Ge66 nuclei with increasing rotational frequency.
dc.identifier.doi10.1103/PhysRevC.100.054330
dc.identifier.endpage-en_US
dc.identifier.issn2469-9985
dc.identifier.issue5en_US
dc.identifier.scopusqualityQ1
dc.identifier.startpage-en_US
dc.identifier.urihttps:/dx.doi.org/10.1103/PhysRevC.100.054330
dc.identifier.urihttps://hdl.handle.net/20.500.12451/7183
dc.identifier.volume100en_US
dc.identifier.wosqualityN/A
dc.indekslendigikaynakWeb of Science
dc.indekslendigikaynakScopus
dc.language.isoen
dc.publisherAmerican Physical Society
dc.relation.ispartofPhysical Review C
dc.relation.publicationcategoryMakale - Uluslararası Hakemli Dergi - Kurum Öğretim Elemanı
dc.rightsinfo:eu-repo/semantics/openAccess
dc.subjectLifetime Measurements
dc.titleLifetime measurements of short-lived excited states, and shape changes in As 69 and Ge 66 nuclei
dc.typeArticle

Dosyalar

Orijinal paket
Listeleniyor 1 - 1 / 1
Küçük Resim
İsim:
matejska-minda-m.-2019.pdf
Boyut:
1.9 MB
Biçim:
Adobe Portable Document Format
Açıklama:
Tam Metin / Full Text
İndir

Koleksiyon

Makale Koleksiyonu
Scopus İndeksli Yayınlar Koleksiyonu
WoS İndeksli Yayınlar Koleksiyonu