SCHOTTKY MASS-SPECTROMETRY AT THE EXPERIMENTAL STORAGE-RING ESR

The application of Schottky beam diagnosis [1] for measurements of nuc lear masses was proposed nearly 10 years ago when injection and electr on cooling of radioactive beams in the Experimental Storage Ring ESR c ame into consideration [3]. Experimental tests of this novel method ha ve been performed recently using electron cooled beams of nuclear frag ments produced in the ring itself by the interaction between different primary beams and the internal gas jet target. Both the relative accu racy and the resolution of mass differences in Schottky spectra proved to be in the low, 1 x 10(-6) range, allowing even the resolution of i someric from ground state masses in some cases. Because of the require d cooling time the spectrometry is applicable, so far, to nuclei with life times of at least a few seconds.