Tessler, M.M.TesslerZappala, J.J.ZappalaCRISTALLO, SergioSergioCRISTALLORoberti, L.L.RobertiPaul, M.M.PaulHalfon, S.S.HalfonHeftrich, T.T.HeftrichJiang, W.W.JiangKijel, D.D.KijelKreisel, A.A.KreiselLIMONGI, MarcoMarcoLIMONGILu, Z. -T.Z. -T.LuMüller, P.P.MüllerPurtschert, R.R.PurtschertReifarth, R.R.ReifarthShor, A.A.ShorVeltum, D.D.VeltumVESCOVI, DiegoDiegoVESCOVIWeigand, M.M.WeigandWeissman, L.L.Weissman2022-03-112022-03-1120212469-9985http://hdl.handle.net/20.500.12386/31551We present a detailed account of neutron capture experiments of astrophysical relevance on <SUP>78,80,84,86<SUP>Kr (n ,γ ) reactions at the border between weak and main s process. The experiments were performed with quasi-Maxwellian neutrons from the Liquid-Lithium Target (LiLiT) and the mA-proton beam at 1.93 MeV (2-3 kW) of the Soreq Applied Research Accelerator Facility (SARAF). The setup yields high-intensity ≈40 keV quasi-Maxwellian neutrons (3-5 ×10<SUP>10</SUP> n /s) closely reproducing the conditions of s -process stellar nucleosynthesis. A sample of 100 mg of atmospheric, pre-nuclear-age Kr gas contained in a Ti spherical shell was activated in the LiLiT neutron field. The abundances of long-lived Kr isotopes (<SUP>81,85 g</SUP>Kr) were measured by atom counting via atom trap trace analysis (ATTA) at Argonne National Laboratory and low-level counting (LLC) at University of Bern. This work is the first measurement of a nuclear cross section using atom counting via ATTA. The activities of short-lived Kr isotopes (<SUP>79,85 m,87</SUP>Kr) were measured by γ -decay counting with a high-purity germanium detector. Maxwellian-averaged cross sections for s -process thermal energies are extracted. By comparison to reference values, our nucleosynthesis network calculations show that the experimental cross sections have a strong impact on calculated abundances of krypton and neighboring nuclides, in some cases improving agreement between theory and observations. <P /></SUP></SUP>STAMPAenArticle10.1103/PhysRevC.104.0158062-s2.0-85111800045WOS:000680431500004https://journals.aps.org/prc/abstract/10.1103/PhysRevC.104.015806https://api.elsevier.com/content/abstract/scopus_id/851118000452021PhRvC.104a5806TFIS/02 - FISICA TEORICA, MODELLI E METODI MATEMATICI