N=82 shell quenching of the classical r-process "waiting-point" nucleus 130Cd

I Dillmann; K-L Kratz; A Wöhr; O Arndt; B A Brown; P Hoff; M Hjorth-Jensen; U Köster; A N Ostrowski; B Pfeiffer; D Seweryniak; J Shergur; W B Walters; ISOLDE Collaboration

doi:10.1103/PhysRevLett.91.162503

N=82 shell quenching of the classical r-process "waiting-point" nucleus 130Cd

Phys Rev Lett. 2003 Oct 17;91(16):162503. doi: 10.1103/PhysRevLett.91.162503. Epub 2003 Oct 16.

Authors

I Dillmann¹, K-L Kratz, A Wöhr, O Arndt, B A Brown, P Hoff, M Hjorth-Jensen, U Köster, A N Ostrowski, B Pfeiffer, D Seweryniak, J Shergur, W B Walters; ISOLDE Collaboration

Affiliation

¹ Institut für Kernchemie, Universität Mainz, Mainz, Germany and Departement für Physik und Astronomie, Universität Basel, Basel, Switzerland.

PMID: 14611397
DOI: 10.1103/PhysRevLett.91.162503

Abstract

First beta- and gamma-spectroscopic decay studies of the N=82 r-process "waiting-point" nuclide 130Cd have been performed at CERN/ISOLDE using the highest achievable isotopic selectivity. Several nuclear-physics surprises have been discovered. The first one is the unanticipatedly high energy of 2.12 MeV for the [pi g(9/2) multiply sign in circle nu g(7/2)] 1(+) level in 130In, which is fed by the main Gamow-Teller transition. The second surprise is the rather high Q(beta) value of 8.34 MeV, which is in agreement only with recent mass models that include the phenomenon of N=82 shell quenching. Possible implications of these new results on the formation of the A approximately 130 r-process abundance peak are presented.