Absence of M2 retardation in Cl-35: Evidence for stronger isospin-mixing effects in A=35 mirror nuclei

The lifetime of the 3163 keV, 7/2− isomeric state in Cl that decays by a stretched M2 transition to the 3/2 ground state, has been re-measured using the Doppler Shift Attenuation Method, by gating on the 1185 keV transition which directly feeds this state. This eliminates the uncertainties in the measurement arising from the direct feedings from the continuum. A mean life of 0.6 −0.2 ps has been obtained from the present work.