One of the current research frontiers in
nuclear physics is the study of unstable nuclei.
This research links Astrophysics and Nuclear
Physics together because unstable nuclei are crucially involved in various astrophysical
events such as supernovae
and X-ray bursts. New many-body
quantum effects are expected to occur in these less-known nuclei. It is
a great challenge for existing nuclear theories that have been designed mainly for
stable nuclei to apply to unstable nuclei.
Dr. Sun's theoretical work
is devoted to the study of these new nuclear mass regions.
Nuclear isomer is a special excited state, in which
structure effects inhibit its decay and endow it with a lifetime that is
remarkably longer than expected. It may be regarded as a storage of nuclear energy. The challenge and potential for scientific discovery
today lie in the understanding of the formation of nuclear isomers (through a better
comprehension of nuclear structure), the ability to excite and de-excite isomers at will
for a broad range of applications,
and the exploration of nuclei with isomeric states in nuclear astrophysics.
Nuclear isomer study is another main focus in Dr. Sun's research.
Dr. Sun's major contribution to the
modern nuclear theory is made through his work
on the development of the Projected Shell Model. His
model solves the nuclear many-body problem by the special projection
techniques, and this model has become a powerful standard
method for understanding nuclear data measured in major nuclear
laboratories worldwide. The algorithms developed for the Projected
Shell Model have found a broad application in the modern
computation for medium to heavy nuclei, and for other quantum many-body systems in general.