Detailed Study of the Decay of ^21Mg

Beta-delayed proton and gamma emission in the decay of ^21Mg has beenmeasured at ISOLDE, CERN with the ISOLDE Decay Station (IDS) set-up. Theexisting decay scheme is updated, in particular what concerns protontransitions to excited states in ^20Ne. Signatures of interference inseveral parts of the spectrum are used to settle spin and parity assignments tohighly excited states in ^21Na. The previously reported βpαbranch is confirmed. A half-life of 120.5(4) ms is extracted for ^21Mg. Therevised decay scheme is employed to test mirror symmetry in the decay and toextract the beta strength distribution of ^21Mg that is compared withtheory.