ISOLDE Seminar

Weak Interaction Studies with 6He

by Andreas Knecht (CERN)

Europe/Zurich
26-1-022 (CERN)

26-1-022

CERN

Description
The Weak nuclear current has two components that behave differently: the vector and axial currents. Understanding the Weak axial current is important for many issues, for example, stellar nucleosynthesis, double-beta decay, and tests of nuclear wave functions. The radioisotope 6He is a particularly attractive system for weak interaction studies due to its half-life of approximately 807 ms, its pure Gamow-Teller transition proceeding close to 100% to the ground state of 6Li and the fact that it is light enough to perform ab-initio calculations with precision. At the University of Washington we developed a high-intensity source of 6He capable of delivering ~10^9 atoms/s to a low-background experimental area. Using this intensity we recently measured the half-life to a precision of 3x10^-4 resolving a long standing discrepancy. This provides a solid basis for comparison with ab-initio calculations modeling the weak interaction in the nucleus. Currently, we are setting up a trapping system consisting of a Zeeman slower and a magneto-optical trap (an additional dipole trap will be added later) and the necessary detectors to perform a measurement of the beta-neutrino angular correlation. This will allow us to search for new physics in the form of tensor contributions to the well established vector and axial-vector structure of the weak interaction.