Speaker
Description
Nuclear fragmentation has been established as one of the most
effective methods for producing fast beams of unstable nuclei at
radioactive beam facilities. In nuclear fragmentation, a projectile
nucleus collides with a target nucleus, producing fragments with
significantly different proton and neutron configurations than the
projectile.
The objective of this study is to understand the reaction mechanism of
fragmentation and explore new methods for producing a wider variety of
unstable beams, including those of isomeric states. The availability
of isomer beams is expected to broaden the scope of nuclear reaction
and structure studies.
The present study focuses on the roles of momentum and angular
momentum transfer in nuclear fragmentation. This was achieved by
investigating the production of nuclei around $^{52}$Fe.
The experiment was performed at the SB2 course of HIMAC in Chiba. The
primary beams of $^{58}$Ni and $^{59}$Co at 350 MeV/u bombarded a
14-mm thick $^{9}$Be target.
Fragments of $^{52}$Fe, $^{53}$Fe, and $^{54}$Co are momentum-analyzed
by a magnetic fragment separator. The de-excitation gamma rays from
$^{52}$Fe(12+), $^{53}$Fe(19/2-), and $^{54}$Co(7+) were detected by
four Ge detectors. Momentum distributions of these high-spin isomeric
states and their ground states were extracted from the data.
By selecting specific isomeric states and comparing their momentum
distributions with those of the ground states, we identified a
correlation between angular momentum and parallel momentum transfer.
This finding is in line with a classical model where the angular
momentum and parallel momentum transfer is modelled as occurring on
the nuclear surface. We also found a correlation between isomeric
ratios and angular momentum transfer.
In this presentation, we summarize these findings and discuss the
current understanding of reaction mechanisms of nuclear fragmentation.
| Type of contribution | poster |
|---|---|
| Are you a student or postdoc? | yes |
