Heavy-ion Elastic Collisions and the Nuclear Surface Diffuseness

Taking the magnitude of the elements of the S matrix and the nuclear phases to be of Woods-Saxon form in the variable I with width parameter LI, we find that the form of the scattering amplitude components f+(B) and f-(B) is specified by the parameters LI+ and LI- such that LI is closely the geometric mean of LI+ and LI-. Many angular distributions have been analysed into f+(B) and f-(B) to obtain LI+ and LI- and hence LI, the angular momentum diffuseness, from which the nuclear surface diffuseness is obtained, so reducing an ambiguity in the nuclear potential. The case of light ions incident on heavy ions has also been investigated.

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Analysis of Angular Distributions of Heavy-ion Transfer Reactions

Australian Journal of Physics ◽

10.1071/ph800965 ◽

1980 ◽

Vol 33 (6) ◽

pp. 965

Author(s):

CBO Mohr

Keyword(s):

Elastic Scattering ◽

Heavy Ions ◽

Heavy Ion ◽

Critical Value ◽

Transfer Reactions ◽

Angular Distributions ◽

Ion Transfer ◽

S Matrix ◽

Low Energies ◽

Nuclear Phases

Proceeding as in our earlier analysis of elastic scattering, but with a form for the S matrix appropriate for transfer, peaked at the critical value Ie and with width parameter .d, it is shown how to analyse the angular distribution of transfer reactions of heavy ions to obtain.d. The effect of the nuclear phases is found not to be of such fundamental importance as in elastic scattering. Analysis of theexperimental data reveals an increase of.d with nuclear size especially at low energies, but an increase of nuclear penetration for transfer collisions of the lightest nuclei. The circumstances in which strong coupling might occur between elastic scattering and transfer are examined.

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Surface diffuseness of nuclear potential from heavy-ion fusion reactions

Nuclear Physics A ◽

10.1016/s0375-9474(03)01412-x ◽

2003 ◽

Vol 722 ◽

pp. C479-C483 ◽

Cited By ~ 13

Author(s):

I.I. Gontchar ◽

D.J. Hinde ◽

M. Dasgupta ◽

J.O. Newton

Keyword(s):

Heavy Ion ◽

Nuclear Potential ◽

Fusion Reactions ◽

Surface Diffuseness ◽

Heavy Ion Fusion

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DYNAMICAL CHANGE OF SURFACE DIFFUSENESS OF ION–ION POTENTIAL AND ITS EFFECT ON FUSION CROSS-SECTION

International Journal of Modern Physics E ◽

10.1142/s0218301313500109 ◽

2013 ◽

Vol 22 (02) ◽

pp. 1350010 ◽

Cited By ~ 7

Author(s):

M. ISMAIL ◽

W. M. SEIF

Keyword(s):

Simple Model ◽

Cross Section ◽

Cross Sections ◽

Fusion Cross Section ◽

Heavy Ion ◽

Nuclear Potential ◽

Physical Processes ◽

Surface Diffuseness ◽

Heavy Ion Fusion ◽

Dynamical Change

We assume a simple model to describe the ion–ion potential with dynamical change in its surface diffuseness. In particular, this model is used to calculate the heavy-ion fusion cross-section using different values of the surface diffuseness. Both the static and dynamic nuclear Woods–Saxon potentials with diffuseness values ranging between 0.65 fm and 1.3 fm are used to reproduce the fusion cross-sections data of the 19 F +208 Pb and 16 O +154 Sm reactions. The results estimate that there are different physical processes which could contribute to the fusion cross-section with different weights at each energy value. Each of these processes has its own nuclear potential.

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Effects of Surface Diffuseness and Coupling Radius Parameters on The Fusion and Quasi-Elastic Barrier Distributions

INDONESIAN JOURNAL OF APPLIED PHYSICS ◽

10.13057/ijap.v9i01.30416 ◽

2019 ◽

Vol 9 (01) ◽

pp. 22

Author(s):

Viska Inda Variani ◽

Ida Usman ◽

Muhammad Zamrun Firihu

Keyword(s):

Heavy Ion ◽

High Energy ◽

Nuclear Potential ◽

Small Surface ◽

Fusion Barrier ◽

Spherical Target ◽

Coupled Channels ◽

Barrier Distribution ◽

Surface Diffuseness ◽

Diffuseness Parameter

We study the heavy-ion reaction at sub-barrier energies for 16O+144,154Smsystems using full order coupled-channels formalism. We especially investigate the effect of fusion and quasi- elastic barrier distributions on the surface diffuseness and the coupling radius parameters of the nuclear potential for these systems. We found that the structure of fusion and quasi-elastic barrier distributions is more sensitive to the surface diffuseness and coupling radius parameters for the reaction with spherical target, 16O+144Sm systemcompared to the reaction that involves the deformed target, i.e., 16O+154Sm system. In more detail, the results of coupled-channels calculations for the fusion and the quasi-elastic barrier distributions for deformed target are not sensitive to the choice of the coupling radius and surface diffuseness parameters. In mark contrast, the structure of the fusion and the quasi-elastic barrier distributions for spherical target are very sensitive to the coupling radius and surface diffuseness parameters. We found that the small surface diffuseness parameter smeared out the fusion barrier distributions and the larger coupling radius smoothed the high energy peak of the quasi-elastic barrier distributions. We also found that the larger coupling radius, , is required by the experimental quasi-elastic barrier distribution for the 16O+144Sm system whereas the experimental fusion barrier distribution compulsory the small value, i.e., .

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Influence of nuclear surface diffuseness on systems involving spherical and deformed targets

International Journal of Modern Physics E ◽

10.1142/s0218301319500526 ◽

2019 ◽

Vol 28 (07) ◽

pp. 1950052

Author(s):

Rajni ◽

Manoj K. Sharma

Keyword(s):

Cross Section ◽

Significant Contribution ◽

Fusion Cross Section ◽

Nuclear Potential ◽

Nuclear Surface ◽

Nucleus Interaction ◽

Pocket Depth ◽

Potential Depth ◽

Surface Diffuseness ◽

Diffuseness Parameter

The effect of diffuseness of nucleus–nucleus interaction potential is tested on the nuclear potential depth, barrier characteristics and fusion excitation functions by considering spherical+spherical and [Formula: see text] colliding partners. It is manifested from the calculations that fusion barrier height and fusion pocket depth get significantly modified with change in diffuseness parameter [Formula: see text] and deeper fusion pocket appears with an increase in the magnitude of diffuseness. We further observed that, depending on the value of [Formula: see text], the fusion pocket depth decreases more sharply for the reactions involving oblate target [Formula: see text] as compared to prolate [Formula: see text] systems, though the overall shift in the pocket (left or right) is almost equal i.e., [Formula: see text]0.5[Formula: see text]fm for both cases. Furthermore, the effect of diffuseness on fusion cross-section is such that, on taking both spherical and/or deformed target-projectile combinations, lower strength of nuclear surface diffuseness (0.60[Formula: see text]fm) seems more suitable upto charge product [Formula: see text] [Formula: see text]200. However, for [Formula: see text], higher value of diffuseness parameter (0.99[Formula: see text]fm) is desirable for systems with spherical as well as deformed target-projectile combinations. Finally, we have explored the effect of angle dependence on the nuclear surface diffuseness within [Formula: see text]C+[Formula: see text]Tb reaction. The study reveals the significant contribution of angular diffuseness in fusion cross-section of reactions involving lanthanide target.

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A nuclear-surface-wave interpretation of quasi-molecular orbiting in heavy-ion collisions

Il Nuovo Cimento A ◽

10.1007/bf02776453 ◽

1980 ◽

Vol 57 (2) ◽

pp. 205-214 ◽

Cited By ~ 5

Author(s):

A. R. Farhan ◽

H. Überall ◽

O. Dragún ◽

E. Maqueda

Keyword(s):

Surface Wave ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

Nuclear Surface ◽

Ion Collisions

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What do angular distributions of subthreshold pions tell us about heavy ion reactions?

10.1063/1.33393 ◽

1982 ◽

Author(s):

Walter Benenson

Keyword(s):

Heavy Ion ◽

Angular Distributions ◽

Heavy Ion Reactions

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Description of (Hyper-)Fragments in Hadron-Induced Reactions

Symmetry ◽

10.3390/sym13101887 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1887

Author(s):

Theodoros Gaitanos

Keyword(s):

Nuclear Reactions ◽

Heavy Ion ◽

Nuclear Fragmentation ◽

Equilibrium Dynamics ◽

Ion Collisions ◽

Light Ions ◽

Classical Transport ◽

Nuclear Targets ◽

Fragmentation Processes

In this article we review the important role of non-equilibrium dynamics in reactions induced by ions and hadron beams to understand the fragmentation processes inside hadronic media. We discuss the single-particle dynamics in specific sources such as spectators in heavy-ion collisions and residual nuclear targets in hadron-induced reactions. Particular attention is given to the dynamics of hyperons. We further discuss the question regarding the onset of local instabilities, which are relevant for the appearance of fragmentation phenomena in nuclear reactions. We apply the theoretical formalism, that is, semi-classical transport embedded with statistical methods of nuclear fragmentation, to reactions induced by light ions and hadron beams. We discuss the results of nuclear fragmentation and, in particular, examine the formation of hypernuclei. Such studies are important for obtaining a deeper understanding of the equation of state in fragmenting matter and are relevant for forthcoming experiments, such as PANDA at FAIR and J-PARC in Japan.

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