Physics Division Seminars bring us speakers on a variety of physics related subjects. Usually these are held in the Building 6008 large Conference Room, at 3:00 pm on the chosen day, but times and locations may vary. For more information, contact our seminar chairman,
Tel (Office): (865) 574-6124 (FAX): (865) 574-1268
I report on our work to measure radii, deformations, and nuclear moments of
nuclei far off stability. These measurements yield information on the
nuclear force and thus test global nuclear models. The research is based on
laser- and rf-spectroscopy on-line to nuclear accelerators at several
laboratories all over the world. Both collinear fast ion beam and ion
storage techniques are being used. For the collinear fast beam, we achieved
a selectivity of one part in 10^10 and a sensitivity of 10^3 ions/s. In ion
storage, ions produced with several 100 MeV energy in a nuclear reaction
were decelerated, then laser cooled to a few meV and stored in an ion trap.
Two new devices, namely the combined linear ion trap and the rf-ion
funnel, were developed for this purpose. In a recent precision
measurement single ion spectroscopy has been demonstrated and has resulted
in the observation of the distribution of the nuclear magnetism in 9Be.
We obtained accuracies of 10-9 for the nuclear spin flip transitions, and
10-7 for the electron spin flip transitions. Future extensions of this
research to the halo nucleus 11Be will be indicated.