کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1850321 | 1528801 | 2016 | 7 صفحه PDF | دانلود رایگان |
The relativistic particle-vibration coupling (RPVC) model is extended by the inclusion of isospin-flip excitation modes into the phonon space, introducing a new mechanism of dynamical interaction between nucleons with different isospin in the nuclear medium. Protons and neutrons exchange by collective modes which are formed by isovector π and ρ-mesons, in turn, softened considerably because of coupling to nucleons of the medium. These modes are investigated within the proton–neutron relativistic random phase approximation (pn-RRPA) and relativistic proton–neutron time blocking approximation (pn-RTBA). The appearance of isospin-flip states with sizable transition probabilities at low energies points out that they are likely to couple to the single-particle degrees of freedom and, in addition to isoscalar low-lying phonons, to modify their spectroscopic characteristics. Such a coupling is quantified for the shell structure of 100,132Sn and found significant for the location of the dominant single-particle states.
Journal: Physics Letters B - Volume 755, 10 April 2016, Pages 138–144