s-process branching atW185revised

Thesprocess: Nuclear physics, stellar models, and observations

“…The isomer in 176 Lu at 123 keV is the key for the interpretation of the mother/daughter ratio of the s-only isotopes 176 Lu and 176 Hf as an s-process thermometer for the He shell flashes in low mass AGB stars (Doll et al, 1999;Klay et al, 1991). At temperatures above about 150 MK the initial population probabilities of isomer (t 1/2 = 3.68 h) and ground state (t 1/2 = 37.5 Gyr) (Heil et al, 2008d;Wisshak et al, 2006b) are altered by a delicate interplay between neutron density and temperature, depending on subtle details in the nuclear structure of 176 Lu (Mohr et al, 2009). The case of 180 Ta is of interest because this is the only isotope in nature, which is (almost) stable in its isomeric state.…”

Cross-Section Measurements of theKr86(γ,n)Reaction to Probe thes-Process Branching atRaut1, Tonchev2, Rusev3 et al. 2013Phys. Rev. Lett.593330View full textAdd to dashboardCite

“…Similar to the analysis of previous (γ,n) measurements of interest to the s-process [18][19][20][21], we carried out statistical model calculations using the TALYS-1.43 code [22,23]. The results of these calculations based on the Hartree-Fock-Bogolyubov (HFB) + quasiparticlerandom-phase approximation (QRPA) γ-ray strength [24], shifted by -0.5 MeV, are also plotted in Fig.…”

Theoretical Photoneutron Cross Sections and the Effect of Gamma Strength Functions for W, Ag, Nb

“…The calculated results are compared with experimentally measured data [25][26][27], taken from EXFOR [21] In the calculations, all of the gamma strength functions of Kopecky-Uhl generalized Lorentzian, Brink-Axel Lorentzian, Hartree-Fock BCS tables, Hartree-FockBogolyubov tables and Goriely's hybrid model have been used. The effects of the gamma strength function on the cross section exchange data have determined the most compatible type of model.…”