Chapter 1
Evolution of Cluster Production with
Fragmentation Degree
E. Bonnet
Abstract We present in this work the experimental production of clusters in the
58 Ni+
58 Ni reactions at incident beam energies between 32 and 90 MeV/nucleon
collected with the INDRA apparatus. We focus on the evolution of their contribution
with respect to the final fragmentation degree given by the charge of the biggest
fragment (Z max ) of each event. Using the mass fraction observable, we look at probabilities of nucleons to be free or bound in clusters and how the different species
evolve with fragmentation degree and with the incident energy of the collision. We
highlight the specific role of the
4 He clusters in the whole range of fragmentation
degree.
1.1 Introduction
Understanding the production of clusters (namely, nucleons ended together) produced in Heavy-ion collisions (HIC) is a very stimulating question. Bringing experimental constraints on that topic should help to constrain both the modelization of
the equation of state (EOS) of non- homogeneous nuclear matter (NM) and also the
treatment of the N-body correlations in transport models.
Many experimental signatures of phase transition in the Fermi energy domain can
be found in literature [1]. According to that, cluster production should be affected
depending on the region of the phase diagram we are looking at. For example, the
spinodal decomposition as the driven process of the phase transition has been recently
confirmed [2]. From that, we should observe the correlated specific behavior for
clusters. In the canonical description of the liquid–gas phase transition, the charge
of the biggest fragment, the Z max observable, has been linked to the order parameter
of this transition [3] and then can be used to sample the phase diagram. Using it, we
can draw easily a continuous evolution between evaporation to vaporization passing
through multifragmentation.
E. Bonnet (B)
SUBATECH, IMTA, CNRS-IN2P3, Nantes, NU, France
e-mail: eric.bonnet@subatech.in2p3.fr
© Springer Nature Singapore Pte Ltd. 2021
R. K. Puri et al. (eds.), Advances in Nuclear Physics, Springer Proceedings
in Physics 257, https://doi.org/10.1007/978-981-15-9062-7_1
1
Evolution of Cluster Production with
Fragmentation Degree
E. Bonnet
Abstract We present in this work the experimental production of clusters in the
58 Ni+
58 Ni reactions at incident beam energies between 32 and 90 MeV/nucleon
collected with the INDRA apparatus. We focus on the evolution of their contribution
with respect to the final fragmentation degree given by the charge of the biggest
fragment (Z max ) of each event. Using the mass fraction observable, we look at probabilities of nucleons to be free or bound in clusters and how the different species
evolve with fragmentation degree and with the incident energy of the collision. We
highlight the specific role of the
4 He clusters in the whole range of fragmentation
degree.
1.1 Introduction
Understanding the production of clusters (namely, nucleons ended together) produced in Heavy-ion collisions (HIC) is a very stimulating question. Bringing experimental constraints on that topic should help to constrain both the modelization of
the equation of state (EOS) of non- homogeneous nuclear matter (NM) and also the
treatment of the N-body correlations in transport models.
Many experimental signatures of phase transition in the Fermi energy domain can
be found in literature [1]. According to that, cluster production should be affected
depending on the region of the phase diagram we are looking at. For example, the
spinodal decomposition as the driven process of the phase transition has been recently
confirmed [2]. From that, we should observe the correlated specific behavior for
clusters. In the canonical description of the liquid–gas phase transition, the charge
of the biggest fragment, the Z max observable, has been linked to the order parameter
of this transition [3] and then can be used to sample the phase diagram. Using it, we
can draw easily a continuous evolution between evaporation to vaporization passing
through multifragmentation.
E. Bonnet (B)
SUBATECH, IMTA, CNRS-IN2P3, Nantes, NU, France
e-mail: eric.bonnet@subatech.in2p3.fr
© Springer Nature Singapore Pte Ltd. 2021
R. K. Puri et al. (eds.), Advances in Nuclear Physics, Springer Proceedings
in Physics 257, https://doi.org/10.1007/978-981-15-9062-7_1
1