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- Jentschel, M., et al.
(författare)
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EXILL - a high-efficiency, high-resolution setup for gamma-spectroscopy at an intense cold neutron beam facility
- 2017
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Ingår i: Journal of Instrumentation. - : IOP PUBLISHING LTD. - 1748-0221. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- In the EXILL campaign a highly efficient array of high purity germanium (HPGe) detectors was operated at the cold neutron beam facility PF1B of the Institut Laue-Langevin (ILL) to carry out nuclear structure studies, via measurements of gamma-rays following neutron-induced capture and fission reactions. The setup consisted of a collimation system producing a pencil beam with a thermal capture equivalent flux of about 10(8) ns(-1)cm(2) at the target position and negligible neutron halo. The targetwas surrounded by an array of eight to ten anti-Compton shielded EXOGAMClover detectors, four to six anti-Compton shielded large coaxial GASP detectors and two standard Clover detectors. For a part of the campaign the array was combined with 16 LaBr3:(Ce) detectors from the FATIMA collaboration. The detectorswere arranged in an array of rhombicuboctahedron geometry, providing the possibility to carry out very precise angular correlation and directional-polarization correlation measurements. The triggerless acquisition system allowed a signal collection rate of up to 6 x 10(5) Hz. The data allowed to set multi-fold coincidences to obtain decay schemes and in combination with the FATIMA array of LaBr3:(Ce) detectors to analyze half-lives of excited levels in the pico-to microsecond range. Precise energy and efficiency calibrations of EXILL were performed using standard calibration sources of Ba-133, Co-60 and Eu-152 as well as data from the reactions Al-27(n, gamma)Al-28 and Cl-35(n,gamma)Cl-36 in the energy range from 30 keV up to 10MeV.
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2. |
- Sanchez-Vega, M., et al.
(författare)
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Studies of quadrupole collectivity in the γ -soft 106Ru
- 2008
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Ingår i: European Physical Journal A. - 1434-6001 .- 1434-601X. ; 35:2, s. 159-165
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Tidskriftsartikel (refereegranskat)abstract
- Various alternative models were used to describe the structure of 106Ru . For example, the General Collective Model (GCM) predicts shape-coexistence for 106Ru with a spherical and a triaxial minimum and strongly mixed structures, while in the IBA-2 calculations, where 106Ru was considered as transitional from vibrational U(5) to γ -soft O(6) , no need was found to include the shape-coexisting configurations. In order to provide additional constraints on the model interpretations, we have applied the Advanced Time-Delayed (ATD) βγγ(t) method to measure the level lifetimes of the excited levels in 106Ru . The new results include the half-lives of T 1/2 = 183(3) ps and 7.5(30)ps for the 2+ 1 and 2+ 2 states, respectively.
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3. |
- Sanchez-Vega, M., et al.
(författare)
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Studies of quadrupole collectivity in the γ -soft 106Ru
- 2008
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Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 35:2, s. 159-165
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Tidskriftsartikel (refereegranskat)abstract
- Various alternative models were used to describe the structure of Ru-106. For example, the General Collective Model (GCM) predicts shape-coexistence for Ru-106 with a spherical and a triaxial minimum and strongly mixed structures, while in the IBA-2 calculations, where Ru-106 was considered as transitional from vibrational U(5) to gamma -soft O(6) , no need was found to include the shape-coexisting configurations. In order to provide additional constraints on the model interpretations, we have applied the Advanced Time-Delayed (ATD) beta gamma gamma(t) method to measure the level lifetimes of the excited levels in Ru-106 . The new results include the half-lives of T-1/2 = 183(3) ps and 7.5(30)ps for the 2(1)(+) and 2(1)(+) states, respectively.
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