Speaker
Prof.
Tomohiro Uesaka
Description
Nuclear physics in the 20th century succeeded in finding regularities in stable
nuclei and in establishing a reasonable picture of a “nucleus”. In 1937, Wigner
presented a picture, referred as “supermultiplet theory”, on a basis of deep
consideration on symmetry in a proton and neutron system. We must be surprised that
Wigner captured an essence of nuclear structure with little knowledge on nucleonnucleon
forces.
In the 21st century, experiments with radioactive nuclear beams, that have
drastically developed since the 1990’s, have revealed that the picture could be valid
locally, namely only in the vicinity of the beta-stability line. Now study of “exotic
nuclei” which locates far from the stability line is at the forefront of nuclear physics
research and has been extensively performed at RI-beam facilities in the world, such
as RI Beam factory in Japan, GSI in Germany, SPIRAL2 in France, and NSCL in
USA.
Why can the structures of exotic nuclei be so different from those of stable nuclei?
The key to understanding is “interplay between spin and isospin”. The interplay can
be naturally figured out in the spirit of the supermultiplet theory when it is combined
with current knowledge of nuclear forces.
In the symposium, I will show the overview of experimental research of exotic
nuclei at RI Beam Factory, putting emphasis on “interplay between spin and isospin
