Low-energy dipole strength in Sn-112,Sn-120
Küçük Resim Yok
Tarih
2014
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
AMER PHYSICAL SOC
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The Sn-112,Sn-120(gamma, gamma') reactions below the neutron separation energies have been studied at the superconducting Darmstadt electron linear accelerator S-DALINAC for different endpoint energies of the incident bremsstrahlung spectrum. Dipole strength distributions are extracted for Sn-112 up to 9.5 MeV and for Sn-120 up to 9.1 MeV. A concentration of dipole excitations is observed between 5 and 8 MeV in both nuclei. Missing strength due to unobserved decays to excited states is estimated in a statistical model. A fluctuation analysis is applied to the photon scattering spectra to extract the amount of the unresolved strength hidden in the background due to fragmentation. The strength distributions are discussed within different model approaches such as the quasiparticle-phonon model and the relativistic time blocking approximation, allowing for an inclusion of complex configurations beyond the initial particle-hole states. While a satisfactory description of the fragmentation can be achieved for sufficiently large model spaces, the predicted centroids and total electric dipole strengths for stable tin isotopes strongly depend on the assumptions about the underlying mean field.
Açıklama
Anahtar Kelimeler
Kaynak
PHYSICAL REVIEW C
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
90
Sayı
2