*
Corresponding author e-mail: kass_phys@aswu.edu.eg
© 2016 NSP
Natural Sciences Publishing Cor.
Quant. Phys. Lett. 5, No. 2, 19-25 (2016) 19
http://dx.doi.org/10.18576/qpl/050202
Real Cluster Folding Potential for α+
40
Ca Elastic Scattering
Zakaria M. M. Mahmoud
1,2
and Kassem. O. Behairy
3,*
1
Physics Department, Faculty of Science, Assiut University, New Valley Branch, Egypt.
2
Physics Department, Philipps University Marburg, D-35032 Marburg, Germany
3
Physics Department, Aswan University, Aswan, Egypt.
Received: 21 Jun. 2016, Revised: 22 Jul. 2016, Accepted: 24 Jul. 2016.
Published online: 1 Aug. 2016.
Abstract: elastic scattering of α+
40
Ca are analyzed in the framework of optical model based on the α-cluster model of
40
Ca.
We adopted an independent α-cluster model to generate the α-cluster and matter densities of
40
Ca. we pre-suggested the
functional form of α-cluster density and fixed its parameters according to the available experimental data about the α-
particle and
40
Ca nuclei. The obtained α-cluster density of
40
Ca is used to generate the real part of the optical potential. The
single folding procedure is used to generate this real optical potential with two different effective α-α interactions. The real
calculated potential supplied with an imaginary squared Woods Saxon potential are used to analyze 20 sets of experimental
data on the energy range between 18 and 166 MeV. We found that our model is successful in reproducing the data for
energies above 40 MeV and still doubtful for lower energies.
Keywords: Optical potential model, single folding, cluster model, α+40Ca elastic scattering.
1 Introduction
Collision between nuclear species is considered as a
powerful way to get information about nuclear interaction
potential and nuclear density. The simplest nuclear
collision process which is considered as the doorway for
other reactions is the elastic scattering. Optical model is
one of the mostly used models for the description of
nuclear scattering especially elastic scattering. The
microscopic description of the nucleus–nucleus optical
model potential is considered as one of the fundamental
tasks in nuclear physics. Good microscopic understanding
of this potential allows, besides understanding the relevant
reaction dynamics involved, predicting optical potentials of
colliding systems for which the elastic scattering
measurement is absent. One of the mostly used methods to
calculate the nucleus-nucleus interaction potential is the
folding model. Folding formulation of the nucleus–nucleus
potential was pioneered by Watanabe [1] in his analysis of
deuteron projectiles.
Through the last few decades folding model calculations
was used for the analysis of scattering processes for a large
number of interacting systems with microscopic and semi-
microscopic approaches. Successfully and intensively
Satchler and Love [2] used double folding (DF) model for
the analysis of light and heavy composite ions scattering.
They used in their analysis DF optical potentials built upon
a realistic effective nucleon–nucleon interaction folded
with the nuclear matter density distributions of projectile
and target nuclei. It is appeared that the beauty of the
folding model lies in its abilities to relate the nuclear
potential to some fundamental quantities, namely nuclear
densities and nucleon-nucleon effective interactions. More
review of this subject can be found in ref. [3].
The DF model based on the point nucleon densities and an
effective nucleon-nucleon interaction is widely and
successfully used to analyze α-nucleus and nucleus-nucleus
elastic scattering [4-9]. Also another approach of the
folding model based on α-cluster picture of the nucleus is
used. This α-cluster based folded potential is used to
analyze the elastic scattering of α-particle and α-like nuclei
from other α-like nuclei [10-13]. This α-cluster picture
dated back to the beginning of nuclear physics through the
explanation of nuclear α-decay from heavy nuclei. For
more details and review about α-clustering in light nuclei
from both experimental and theoretical point of view see
ref. [14,15] and references therein.
Previously, the present α-cluster folding model was used
successfully to describe the α-nucleus [16] and nucleus–
nucleus scattering [17]. The interaction potentials between
Quantum Physics Letters
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