Low-energy enhancement and fluctuations of $γ$-ray strength functions in $^{56,57}$Fe: test of the Brink-Axel hypothesis
Abstrak
Nuclear level densities and $γ$-ray strength functions of $^{56,57}$Fe have been extracted from proton-$γ$ coincidences. A low-energy enhancement in the $γ$-ray strength functions up to a factor of 30 over common theoretical E1 models is confirmed. Angular distributions of the low-energy enhancement in $^{57}$Fe indicate its dipole nature, in agreement with findings for $^{56}$Fe. The high statistics and the excellent energy resolution of the large-volume LaBr$_{3}$(Ce) detectors allowed for a thorough analysis of $γ$ strength as function of excitation energy. Taking into account the presence of strong Porter-Thomas fluctuations, there is no indication of any significant excitation-energy dependence in the $γ$-ray strength function, in support of the generalized Brink-Axel hypothesis.
Topik & Kata Kunci
Penulis (24)
A. C. Larsen
M. Guttormsen
N. Blasi
A. Bracco
F. Camera
L. Crespo Campo
T. K. Eriksen
A. Görgen
T. W. Hagen
V. W. Ingeberg
B. V. Kheswa
S. Leoni
J. E. Midtbø
B. Million
H. T. Nyhus
T. Renstrøm
S. J. Rose
I. E. Ruud
S. Siem
T. G. Tornyi
G. M. Tveten
A. V. Voinov
M. Wiedeking
F. Zeiser
Akses Cepat
- Tahun Terbit
- 2016
- Bahasa
- en
- Sumber Database
- arXiv
- Akses
- Open Access ✓