Research

Dr Eddie Paul

Ph. D., M. InstP, CPhys

Research Interest 1

My research involves the nuclear structure of medium-mass nuclei (A=100-160) at very high spin (angular momentum). Gamma-ray spectroscopic studies of these nuclei are performed using large
multidetector arrays of hyperpure germanium detectors (e.g. GAMMASPHERE, EXOGAM, JUROGAM)
at international laboratories in both Europe and the USA.

A major question is how the nucleus, a finite fermionic or mesoscopic system, generates angular momentum at ultra-high spin? The finite nature of the nucleus leads to the observation of "band termination" when all of the nuclear angular momentum is generated by the single-particle spin of a number of valence particles outside an inert doubly magic closed core. However, spin generation beyond band termination has been the subject of debate and experimental investigation for more than two decades. Very recently we have found evidence for very weakly populated structures extending well beyond band termination, up to spin 65 hbar, in erbium nuclei. These structures are based on strongly deformed "triaxial" nuclear shapes which are formed when extra particles are ripped out of the closed core.

Other topics of my research include:
the mechanism and decay out of "superdeformed" band structures; chiral symmetry and anomalous signature inversions in odd-odd nuclei;
the spectroscopy of maximally deformed, extremely neutron-deficient rare-earth nuclei using
Radioactive Ion Beams beams at GANIL;
Recoil-Decay Tagging experiments for light Te, I, Xe and Cs nuclei performed at Jyvaskyla.