Conversion electron-gamma coincidences and intrinsic reflection asymmetry in Ra-219 - art. no. 021301

The band structure of Ra-219 has been studied via the Pb-208(C-14,3n) react ion using both gamma-gamma and conversion electron-gamma coincidence measur ements. This nucleus is at the lower mass limit of a region where static oc tupole deformation may occur. The conversion coefficients of seven transiti ons and two upper limits on conversion coefficients have been determined fo r the first time. The results establish the alternating parity nature of a sideband in this nucleus and also resolve an apparent conflict between radi oactive decay data and heavy-ion reaction data. The resulting level scheme of Ra-219 can be explained either by intermediate coupling of the odd neutr on to a reflection symmetric core and a low frequency octupole vibrational mode or by strong coupling to a statically octupole deformed core.