TILTED FOIL POLARIZATION OF RADIOACTIVE IONS

The tilted foil polarization technique has been applied to a beam of r adioactive Mg-23 (I = 3/2 T-1/2 = 11.35 s) ions from ISOLDE. To achiev e sufficient energy for penetration of the foils a high voltage platfo rm has been constructed and used far acceleration of the initial 120 k eV beam of 2(+) Mg-23 ions to 480 keV. The resulting asymmetry epsilon of the emitted beta-radiation from the Mg-23 implanted into a cold Pt stopper has been measured as a function of a holding magnetic field. At B = 0.09 T a value of epsilon = -7.4(1) X 10(-3) was found. The asy mmetry was reduced to epsilon = -3.3(4) X 10(-3) at a field below 0.00 5 T. It is argued that this hard core asymmetry occurs as a result of the internal interaction between the polarized nuclei and the defects created in the implantation process.