| Autor: |
N. Bernier, Aaron Chester, J. Williams, A. B. Garnsworthy, O. Paetkau, L. J. Evitts, F.H. Garcia, S. Hallam, K. Starosta, G. Hackman, Panu Ruotsalainen, U. Rizwan, C. E. Svensson, T.E. Drake, Elizabeth Padilla-Rodal, K. Van Wieren, E. Macconnachie, G. C. Ball, J. K. Smith, J. L. Pore, J. Shoults, Jack Henderson, James Smallcombe, M. Williams, D. S. Cross, R. Henderson, R. Krücken, T. Domingo, M. Moukaddam |
| Rok vydání: |
2018 |
| Předmět: |
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| Zdroj: |
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 882:69-83 |
| ISSN: |
0168-9002 |
| DOI: |
10.1016/j.nima.2017.11.029 |
| Popis: |
The TIGRESS Integrated Plunger device (TIP) has been developed for recoil distance method (RDM) lifetime measurements using the TIGRESS array of HPGe γ -ray detectors at TRIUMF’s ISAC-II facility. A commissioning experiment was conducted utilizing a 250 MeV 84Kr beam at ≈ 2 × 1 0 8 particles per second. The 84Kr beam was Coulomb excited to the 2 1 + state on a movable 27Al target. A thin Cu foil fixed downstream from the target was used as a degrader. Excited nuclei emerged from the target and decayed by γ -ray emission at a distance determined by their velocity and the lifetime of the 2 1 + state. The ratio of decays which occur between the target and degrader to those occurring after traversing the degrader changes as a function of the target–degrader separation distance. Gamma-ray spectra at 13 target–degrader separation distances were measured and compared to simulated lineshapes to extract the lifetime. The result of τ = 5 . 541 ± 0 . 013 (stat.) ± 0 . 063 (sys.) ps is shorter than the literature value of 5 . 84 ± 0 . 18 ps with a reduction in uncertainty by a factor of approximately two. The TIP plunger device, experimental technique, analysis tools, and result are discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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Full Text from ScienceDirect