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

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.

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

2013 ◽  
Vol 22 (02) ◽  
pp. 1350010 ◽  
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.

scholarly journals Heavy-ion Elastic Collisions and the Nuclear Surface Diffuseness

1979 ◽  
Vol 32 (6) ◽  
pp. 541
Author(s):  
CBO Mohr
Keyword(s):  
Scattering Amplitude ◽  
Geometric Mean ◽  
Heavy Ion ◽  
Nuclear Potential ◽  
Angular Distributions ◽  
Nuclear Surface ◽  
S Matrix ◽  
Light Ions ◽  
Surface Diffuseness ◽  
Nuclear Phases

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.

Effect of Surface Diffuseness Parameter on Quasi-elastic Scattering Calculations for 16O+208Pb,63Cu Systems

2021 ◽  
Vol 19 (10) ◽  
pp. 100-105
Author(s):  
Nagham H. Hayef ◽  
Khalid S. Jassim
Keyword(s):  
Relative Motion ◽  
Cross Sections ◽  
Single Channel ◽  
Nuclear Potential ◽  
Channel Calculation ◽  
Coupled Channels ◽  
Coupled Channel Calculation ◽  
Surface Diffuseness ◽  
Diffuseness Parameter ◽  
Coupled Channel

A systematic study on the surface characteristic of the nucleus-nucleus potential for some heavy-ion. The nuclear potential has been described by using Woods-Saxon (WS), the single-channel (SC) and the coupled-channels (CC) calculations, which were between the relative motion of the colliding nuclei and their intrinsic motions, were conducted to study its influence on calculation, the ratio of the quasi-elastic to the Rutherford cross sections and probe the surface diffuseness method was used to find the best fitted value of the diffuseness parameters in comparison with the experimental data. We find that the best fitted value of the diffuseness parameter which obtained through a coupled-channel calculation with inert target and excited projectile forIn the current work, the single-channel (SC) and the coupled-channels (CC) calculations, which were between the relative motion of the colliding nuclei and their intrinsic motions, were conducted to study its influence on calculation, the ratio of the quasi-elastic to the Rutherford cross sections and probe the surface diffuseness find that the best fitted value of the diffuseness parameter which obtained through a coupled-channel calculation with excited target and projectile excited also inert projectile-excited target for the 16O+208Pb andexcited projectile and inert target for the 16O+63Cu.

scholarly journals A comprehensive analysis of 9Li + 70Zn fusion cross section by using proximity potentials, temperature dependent density distributions and nuclear potentials

2019 ◽  
Vol 65 (5 Sept-Oct) ◽  
pp. 573
Author(s):  
M. Aygun ◽  
Z. Aygun
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Cross Sections ◽  
Fusion Cross Section ◽  
Comprehensive Analysis ◽  
Nuclear Potential ◽  
Saxon Potential ◽  
Temperature Dependent ◽  
Density Distributions ◽  
Dependent Density

The fusion cross section of $^{9}$Li + $^{70}$Zn reaction is studiedin an extensive manner within the framework of different theoreticalapproaches. For this purpose, three different methods which consistof proximity potentials, temperature dependent densities andtemperature dependent nuclear potentials are used in order todetermine the real part of the nuclear potential. The imaginary partis considered as Woods-Saxon potential. The calculated fusion crosssections are compared with the experimental data. The theoreticalresults describe the experimental data very well. It is seen thatthe applied approaches present to be different ways to study thereactions involving fusion cross sections.

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

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 <sup>16</sup>O+<sup>144,154</sup>Smsystems 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, <sup>16</sup>O+<sup>144</sup>Sm systemcompared to the reaction that involves the deformed target, i.e., <sup>16</sup>O+<sup>154</sup>Sm 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 <sup>16</sup>O+<sup>144</sup>Sm system whereas the experimental fusion barrier distribution compulsory the small value, i.e., .

Role of constant value of surface diffuseness in alpha decay half-lives of superheavy nuclei

2018 ◽  
Vol 33 (14) ◽  
pp. 1850080 ◽  
Author(s):  
V. Dehghani ◽  
S. A. Alavi ◽  
Kh. Benam
Keyword(s):  
Alpha Decay ◽  
Tunneling Probability ◽  
Nuclear Potential ◽  
Superheavy Nuclei ◽  
Wkb Method ◽  
Alpha Emitters ◽  
Surface Diffuseness ◽  
Diffuseness Parameter ◽  
Good Agreement

By using WKB method and considering deformed Woods–Saxon nuclear potential, deformed Coulomb potential, and centrifugal potential, the alpha decay half-lives of 68 superheavy alpha emitters have been calculated. The effect of the constant value of surface diffuseness parameter in the range of 0.1 [Formula: see text]a [Formula: see text] 0.9 (fm) on the potential barrier, tunneling probability, assault frequency, and alpha decay half-lives has been investigated. Significant differences were observed for alpha decay half-lives and decay quantities in this range of surface diffuseness. Good agreement between calculated half-lives with fitted surface diffuseness parameter a = 0.54 (fm) and experiment was observed.

ANALYSIS OF NUCLEUS–NUCLEUS FUSION CROSS-SECTION AT EXTREME SUB-BARRIER ENERGIES

2012 ◽  
Vol 21 (07) ◽  
pp. 1250067 ◽  
Author(s):  
BASUDEB SAHU ◽  
BIDHUBHUSAN SAHU
Keyword(s):  
Elastic Scattering ◽  
Cross Section ◽  
Optical Potential ◽  
Potential Model ◽  
Fusion Cross Section ◽  
Analytical Form ◽  
Heavy Ion ◽  
Barrier Energy ◽  
Barrier Potential ◽  
Surface Diffuseness

The nucleus–nucleus potential is expressed phenomenologically by a new radial form as an alternative to the conventional Woods–Saxon form. By virtue of novel representation of the surface diffuseness, the potential added with the electrostatic part generates a unique barrier potential which provides simultaneous explanations of two important mechanisms namely elastic scattering and fusion in a heavy-ion reaction within the framework of optical potential model of scattering and region-wise absorption in analytical form. The drastic falloff of experimental results of fusion cross-section (σ fus ) at extreme sub-barrier energy (E) and its manifestation depicting maximum in S( = Eσ fus e2πη) factor and steep rise in L( = d ln (Eσ fus )/dE) factor are explained with remarkable success.

DEUTERON-NUCLEUS INTERACTION AT INTERMEDIATE ENERGIES

1994 ◽  
Vol 03 (01) ◽  
pp. 149-170 ◽  
Author(s):  
YU. A. BEREZHNOY ◽  
V. YU. KORDA
Keyword(s):  
Cross Sections ◽  
Reaction Cross ◽  
Nuclear Surface ◽  
Nuclear Radius ◽  
Vibrational States ◽  
Nucleus Interaction ◽  
Intermediate Energies ◽  
Interaction Processes ◽  
Surface Diffuseness ◽  
Reaction Cross Sections

The deuteron-nucleus interaction has been studied in the approximation where the deuteron radius and the nuclear surface diffuseness are small compared with the nuclear radius. The closed formulae have been derived for the integrated cross-sections of different deuteron-nucleus interaction processes and for differential cross-sections of the deuteron elastic scattering and the deuteron inelastic scattering with excitation of the low lying vibrational states of nuclei. It is shown that the allowance for nuclear surface diffuseness substantially influences the values of the different deuteron-nucleus reaction cross-sections.

Fusion and Breakup Reactions of 17S + 208Pb and 15C + 232ThHalo Nuclei Systems

2015 ◽  
Vol 11 (2) ◽  
pp. 2972-2978
Author(s):  
Fouad A. Majeed ◽  
Yousif A. Abdul-Hussien
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Fusion Reaction ◽  
Fusion Cross Section ◽  
Reaction Cross ◽  
Recent Experimental Data ◽  
Barrier Distribution ◽  
Coupled Channel ◽  
Total Fusion ◽  
Full Quantum

In this study the calculations of the total fusion reaction cross section have been performed for fusion reaction systems 17F + 208Pb and 15C + 232Th which involving halo nuclei by using a semiclassical approach.The semiclassical treatment is comprising the WKB approximation to describe the relative motion between target and projectile nuclei, and Continuum Discretized Coupled Channel (CDCC) method to describe the intrinsic motion for both target and projectile nuclei. For the same of comparsion a full quantum mechanical clacualtions have been preforemd using the (CCFULL) code. Our theorticalrestuls are compared with the full quantum mechaincialcalcuations and with the recent experimental data for the total fusion reaction  checking the stability of the distancesThe coupled channel calculations of the total fusion cross section σfus, and the fusion barrier distribution Dfus. The comparsion with experiment proves that the semiclassiacl approach adopted in the present work reproduce the experimental data better that the full quantal mechanical calcautions. 

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