scholarly journals Decay of 160Er* in 16O + 144Nd and 64Ni + 96Zr Fusion Reactions

2019 ◽  
Vol 7 ◽  
pp. 137
Author(s):  
N. G. Nicolis ◽  
J. L. Barreto ◽  
D. G. Sarantites ◽  
R. J. Charity ◽  
L. G. Sobotka ◽  
...  
Keyword(s):  
Compound Nucleus ◽  
Cross Sections ◽  
Detection System ◽  
Good Description ◽  
Evaporation Residue ◽  
Fusion Reactions ◽  
Fusion Model ◽  
Fusion Data ◽  
Spin Distributions ◽  
Bombarding Energy

The population of evaporation residue entry states in the decay of the compound nucleus 160Er*(54 MeV) is investigated in a cross-bombardment employing the reactions 160 + 144Nd and 64Ni + 96Zr. Evaporation residue cross sections and entry state 7-ray fold distributions of the dominant exit channels were obtained for each reaction, using a 4π 7-ray detection system. An entrance-channel dependence of the 7-ray fold distributions of the xn products is observed. This effect is described successfully by the statistical model making use of compound nucleus angular momentum distributions obtained with a fusion model that provides a good description of the bombarding energy dependence of fusion data for both reactions. In accordance with recent findings on the decay of 164Yb*, it is suggested that the observed differences in the population of the dominant exit channels originate from the primary spin distributions rather than a possible dependence of the compound nucleus decay on the formation mode.

COLD FUSION REACTIONS USING NEUTRON-RICH PROJECTILES

2013 ◽  
Vol 22 (08) ◽  
pp. 1350061 ◽  
Author(s):  
A. SULAKSONO
Keyword(s):  
Cross Section ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Estimation Method ◽  
Cold Fusion ◽  
Evaporation Residue ◽  
Fusion Reactions ◽  
Fusion Barrier ◽  
The Cross ◽  
Evaporation Residues

This paper studies the formation cross-sections of super heavy (SH) nuclei in some cold fusion reactions of radioactive neutron-rich projectiles with double-magic 208 Pb target. In this study, the cross-sections of capture, fusion and evaporation residues in one- and two-neutron (1n and 2n) channels are calculated by using neutron-rich Fe , Ni and Zn projectiles are compared to the cross-sections calculated using stable Fe , Ni and Zn projectiles. The heights of fusion barrier and their positions in all reactions considered in this study are also compared to the heights and positions calculated using the estimation method proposed by Dutt and Puri. For cold fusion reactions with stable Fe , Ni and Zn projectiles, the heights of fusion barrier and the cross-sections of evaporation residues in 1n and 2n channels are compared to their corresponding experimental data. In general, for reactions using projectiles with the same proton number, the neutron-rich projectile is found to yield relatively-heavier mass of SH nucleus and larger evaporation residue cross-section, compared to those of the corresponding stable projectiles. However, in certain reactions, the cross-sections of neutron-rich projectile can be slightly larger or slightly smaller than that of the corresponding stable projectile. This behavior is highly affected by the charge of projectile and the fission barrier of the formed compound nucleus (CN). In addition, the 292114 is found to be the heaviest compound nucleus formed in cold fusion reaction by using neutron-rich nuclei as the projectile, but the cross-section of evaporation residue in one-neutron channel is still around few pico barns (pb).

MEASURING CAPTURE CROSS SECTIONS FOR HEAVY-ELEMENT PRODUCTION

2004 ◽  
Vol 13 (01) ◽  
pp. 293-300
Author(s):  
NEIL ROWLEY ◽  
NABILA GRAR
Keyword(s):  
Cross Section ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Reaction Path ◽  
Superheavy Element ◽  
Evaporation Residue ◽  
Capture Cross ◽  
Total Capture ◽  
Capture Cross Sections

The creation of the nucleus of a superheavy element follows an extremely complex reaction path starting with the crossing of an external potential barrier (or distribution of barriers). This is followed by the evolution towards an equilibrated compound nucleus, which takes place in competition with pre-compound-nucleus fission (quasi-fission). Once formed the equilibrated compound nucleus must still survive against true fusion to yield a relatively long-lived evaporation residue. Much of this path is poorly understood, though recently, progress has been made on the role of the entrance-channel in quasi-fission. This will be briefly reported and a method proposed to measure the total capture cross section for such systems directly.

CALCULATIONS OF CROSS SECTIONS FOR THE SYNTHESIS OF SUPER-HEAVY NUCLEI IN COLD FUSION REACTIONS

2004 ◽  
Vol 13 (01) ◽  
pp. 261-267 ◽  
Author(s):  
W. J. ŚWIATECKI ◽  
K. SIWEK-WILCZYŃSKA ◽  
J. WILCZYŃSKI
Keyword(s):  
Cross Section ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Free Parameter ◽  
Cold Fusion ◽  
One Dimension ◽  
Brownian Diffusion ◽  
Heavy Nuclei ◽  
Fusion Reactions ◽  
Super Heavy Nuclei

The fusion cross sections are considered to be given by the product of three factors: the cross section to overcome the Coulomb barrier, the probability for the resulting system to reach the compound nucleus configuration by diffusion, and the probability for the compound nucleus to survive fission. The first and third factors are treated by more or less conventional equations, and the second by Brownian diffusion in one dimension. Adjusting one free parameter in the theory one can reproduce the twelve measured cross sections to within a factor of two.

Investigations on 54–60Fe + 238–244Pu → 296–302120 fusion reactions

2020 ◽  
pp. 1-8
Author(s):  
H.C. Manjunatha ◽  
L. Seenappa ◽  
N. Sowmya ◽  
K.N. Sridhar
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Survival Probability ◽  
Superheavy Element ◽  
Evaporation Residue ◽  
Superheavy Nuclei ◽  
Fusion Reactions ◽  
Compound Nucleus Formation ◽  
Evaporation Residue Cross Section ◽  
Target Combination

We have studied the 54–60Fe-induced fusion reactions to synthesize the superheavy nuclei296–302120 by studying the compound nucleus formation probability, survival probability, and evaporation residue cross-sections. The comparison of the evaporation residue cross-section for different targets reveals that the evaporation residue cross-section is larger for projectile target combination 58Fe+243Pu→301120. We have identified the most probable 58Fe-induced fusion reactions to synthesize superheavy nuclei 296–302120. The suggested reactions may be useful to synthesize the superheavy element Z = 120.

Fusion-fission and neutron-evaporation-residue cross-sections in 40Ar- and 50Ti-induced fusion reactions

1984 ◽  
Vol 419 (3) ◽  
pp. 571-588 ◽  
Author(s):  
H.-G. Clerc ◽  
J.G. Keller ◽  
C.-C. Sahm ◽  
K.-H. Schmidt ◽  
H. Schulte ◽  
...  
Keyword(s):  
Cross Sections ◽  
Evaporation Residue ◽  
Fusion Reactions ◽  
Neutron Evaporation

scholarly journals Heavy-ion fusion reactions at extreme sub-barrier energies

2021 ◽  
Vol 57 (7) ◽  
Author(s):  
C. L. Jiang ◽  
B. B. Back ◽  
K. E. Rehm ◽  
K. Hagino ◽  
G. Montagnoli ◽  
...  
Keyword(s):  
Cross Sections ◽  
Good Description ◽  
Fusion Cross Section ◽  
Heavy Ion ◽  
New Physics ◽  
Fusion Reactions ◽  
Theoretical Approaches ◽  
Medium Mass ◽  
The Status ◽  
Heavy Ion Fusion

AbstractThe study of fusion reactions at extreme sub-barrier energies has seen an increased interest in recent years, although difficult to measure due to their very small cross sections. Such reactions are extremely important for our understanding of the production of heavy elements in various environments. In this article, the status of the field is reviewed covering the experimental techniques, the available data, and the theoretical approaches used to describe such reactions. The fusion hindrance effect, first discovered in medium-mass systems, has been found to be relevant also for lighter systems. In some light systems, resonance structures are found to be important, while for heavy systems, the fission process plays an important role. In the near barrier region, couplings to collective excitations in the fusion participants and transfer reactions have been found to give a good description of the measured fusion cross sections and it results in a distribution of fusion barrier heights. New physics ingredients, related to the overlap process of the two projectiles, have to be introduced to describe the hindrance behavior. In addition, it has recently been found that the fusion cross section in both near-barrier and sub-barrier regions can be described very well in many cases using simple, analytical forms of the barrier-height distributions or a modified version of the classic Wong formula.

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