Oliver Wieland
Research activity:
“Google scholar index” of O. Wieland)
”Web_of_Science”_LIST_of_Publications
of O. Wieland”
My main research activity is in the field of nuclear
structure physics doing experimental investigations, theoretical evaluations
and technical developments.
My experimental research
is presently carried out at various laboratories such as LNL/LNS
in Legnaro/Catania (Italy), GSI
(Darmstadt-Germany), GANIL
(Caen-France), RIKEN
(Tokyo-Japan) and Argonne National Lab.
(Chicago-USA), using stable and radioactive beams and targets.
The Giant Dipole Resonance (GDR) can be described
macroscopically as a collective excited state consisting in an oscillation of
neutrons against protons in counter phase. Microscopically it can be described
as a coherent superposition of particle-hole excitations.
Experimentally the GDR has been studied both at zero temperature by photoabsorption measurements and at finite temperature in
the decay of nuclei populated using heavy ion reactions.
The properties of the GDR are directly related to the temperature, spin of the
rotating nucleus, neutron excess and isospin symmetry and are currently
investigated in a campaign of experiments with both stable and radioactive
beams.
With Exotic Nuclei I investigate the shell structure
and collective excitations of nuclei far from the stability line. This has
become a key topic of nuclear structure in recent years. Shells and sub-shells
may differ significantly from those established from well-known nuclei near the
valley of stability, especially as the number of neutrons is increased.
Collective excitations are expected to fragment and shift their strength to
lower energy Pygmy Dipole Resonances (PDR). It is a very difficult task to
access experimentally such kind of neutron rich nuclei
as the production cross sections decreases exponentially as we approach the
neutron drip line. Only very recently, new Radioactive Beam Facilities have
given the possibility to produce and excite such nuclei far from the stability
line.
The RISING/PRESPEC
project at GSI
in Germany and Eurica/Sunflower
project at RIKEN in
Japan are intended to perform high resolution g-ray spectroscopy using
the radioactive beam facility at GSI and RIKEN. Unstable beams at energies
ranging from 100 up to 600 A·MeV are produced by
fragmentation of relativistic heavy ion projectiles provided by the SIS
synchrotron or RIBF. The
fragment separator FRS or BigRIPS are used to select and focus the exotic
fragments on a secondary target where arrays of HPGe, LaBr3:Ce
and BaF2
detectors are located. Charged particle detectors and magnets enable an
event-by-event tracking of the incoming radioactive projectiles and the
reaction products, thus allowing for a selection of nuclei of interest and
velocity reconstruction.
My research activity is reflected in
various invited lectures and publications as can be seen in the following
links:
Other
links of possible interest:
·
lezioni (school) 1, 2,
3, 4
·
corso (university
lesson-course)
·
mix
TOOLS
DynamicDIPOLE
NUCLEAR STRUCTURE EXPERIMENTAL
GROUP old PAGE®
NUCLEAR STRUCTURE
EXPERIMENTAL GROUP new PAGE®
cv. e-mail: wieland@mi.infn.it
Internet phone: 