Parts | Days | Selection | Search | Downloads | Help

HK: Fachverband Hadronen und Kerne

HK 26: Nuclear Structure and Dynamics I

HK 26.4: Talk

Tuesday, March 17, 2009, 15:15–15:30, H-ZO 40

High resolution (³He,t) reaction on ⁷⁶Ge and implications to double β decay — •Jan H. Thies, Dieter Frekers, Eike-W. Grewe, Pia Heinrichs, Peter Puppe, and Tim Ruhe — Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Straße 9, 48149 Münster

A high-resolution ⁷⁶Ge(³He,t)⁷⁶As measurement was performed at RCNP in Osaka (Japan) using the ³He beam at an incident energy of 420 MeV and the high resolution WS course beam line. An energy resolution of 27 keV was achieved.

The measured data were used to extract the GT⁻ strength in ⁷⁶As, which is the intermediate nucleus in the double β decay of ⁷⁶Ge. We observe that the GT⁻ strength up to 5 MeV is highly fragmented. To construct the 2νββ decay matrix element for ⁷⁶Ge, these data are then combined with GT⁺ data from a ⁷⁶Se(d,²He)⁷⁶As measurement performed at KVI in Groningen (Netherlands). We note a strong level-by-level anti-correlation, which we attribute to the difference of the intrinsic deformation of the two nuclei, ⁷⁶Ge and ⁷⁶Se. We will discuss the implications on the matrix element of the ⁷⁶Ge 2νββ decay.