COLD FUSION REACTIONS USING NEUTRON-RICH PROJECTILES

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).

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

International Journal of Modern Physics E ◽

10.1142/s021830130400203x ◽

2004 ◽

Vol 13 (01) ◽

pp. 261-267 ◽

Cited By ~ 13

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.

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MEASURING CAPTURE CROSS SECTIONS FOR HEAVY-ELEMENT PRODUCTION

International Journal of Modern Physics E ◽

10.1142/s0218301304002077 ◽

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.

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Effects of level density parameter on the superheavy production in cold fusion

Modern Physics Letters A ◽

10.1142/s0217732314502149 ◽

2014 ◽

Vol 29 (40) ◽

pp. 1450214 ◽

Cited By ~ 4

Author(s):

M. R. Pahlavani ◽

S. A. Alavi

Keyword(s):

Cross Section ◽

Neutron Emission ◽

Level Density ◽

Cold Fusion ◽

Heavy Ion ◽

Evaporation Residue ◽

Density Parameter ◽

Fusion Reactions ◽

Level Density Parameter ◽

Evaporation Residue Cross Section

By using semiclassical method and considering Woods–Saxon and Coulomb potentials, the level density parameter a was calculated for three superheavy nuclei 270110, 278112 and 290116. Obtained results showed that the value of level density parameter of these nuclei is near to the simple relation a ≈ A/10. In framework of the dinuclear system model, the effects of level density parameter on the probability of the formation of a compound nucleus, the ratio of neutron emission width and fission width, and evaporation residue cross-section of three cold fusion reactions 62 Ni +208 Pb , 70 Zn +208 Pb and 82 Se +208 Pb , leading to superheavy elements were investigated. The findings indicate that the level density parameter play a significant role in calculations of heavy-ion fusion–fission reactions. The obtained results in the case of a = A/12 have larger values in comparison with calculated level density parameter with Woods–Saxon potential (a WS ) and a = A/10. The theoretical results of the evaporation residue cross-section are very sensitive to the choice of level density parameter. The calculated values with a WS are in good agreement with experimental values.

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

Canadian Journal of Physics ◽

10.1139/cjp-2019-0580 ◽

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.

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Ein einfaches Modell zum Vergleich der Theorien von Hauser-Feshbach und P. A. Moldauer

Zeitschrift für Naturforschung A ◽

10.1515/zna-1968-0701 ◽

1968 ◽

Vol 23 (7) ◽

pp. 955-961

Author(s):

F. Schmidt

Keyword(s):

Elastic Scattering ◽

Cross Section ◽

Compound Nucleus ◽

Cross Sections ◽

Channel Model ◽

Open Channels ◽

Nucleus Formation ◽

Compound Nucleus Formation ◽

The Cross

We discuss and compare the theories of HAUSER and FESHBACH and P. A. MOLDAUER by a simple two channel model. It is found that after a good fit of parameters only the cross sections of compound-elastic scattering differ substantially. Most differences appear if there are a few open channels. The consequences for the cross section of compound nucleus formation and also for calculations by the evaporation mdel are considered. By our model an evident foundation is given for the statement that MOLDAUER'S theorie would be valid for 〈Γλc〉/D ≦ 1.

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

HNPS Proceedings ◽

10.12681/hnps.2410 ◽

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.

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Experimental Studies Of Multilayer Glass Structures On Compression, Compression With Bending And Simple Bending

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.01.22-30 ◽

2019 ◽

pp. 22-30

Keyword(s):

Cross Section ◽

Cross Sections ◽

Applied Load ◽

Experimental Studies ◽

Strength Properties ◽

Research Topic ◽

Normative Values ◽

Laminated Glass ◽

The Cross ◽

Experimental Values

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.

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Total cross sections of eγ → $$ eX\overline{X} $$ processes with X = μ, γ, e via multiloop methods

Journal of High Energy Physics ◽

10.1007/jhep01(2021)144 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Roman N. Lee ◽

Alexey A. Lyubyakin ◽

Vyacheslav A. Stotsky

Keyword(s):

Cross Section ◽

Cross Sections ◽

Elliptic Integral ◽

High Energy ◽

Calculation Methods ◽

Complete Elliptic Integral ◽

Total Cross Sections ◽

Multiloop Calculation ◽

The Cross ◽

Analytical Expressions

Abstract Using modern multiloop calculation methods, we derive the analytical expressions for the total cross sections of the processes e−γ →$$ {e}^{-}X\overline{X} $$ e − X X ¯ with X = μ, γ or e at arbitrary energies. For the first two processes our results are expressed via classical polylogarithms. The cross section of e−γ → e−e−e+ is represented as a one-fold integral of complete elliptic integral K and logarithms. Using our results, we calculate the threshold and high-energy asymptotics and compare them with available results.

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Asymptotic Behavior of Stable Structures Made of Beams

Journal of Elasticity ◽

10.1007/s10659-021-09816-w ◽

2021 ◽

Author(s):

Georges Griso ◽

Larysa Khilkova ◽

Julia Orlik ◽

Olena Sivak

Keyword(s):

Asymptotic Behavior ◽

Cross Section ◽

Cross Sections ◽

Linear Elasticity ◽

Circular Cross Section ◽

Linear Elasticity Theory ◽

Linear Elastic ◽

The Cross ◽

Small Rotation ◽

Stable Structures

AbstractIn this paper, we study the asymptotic behavior of an $\varepsilon $ ε -periodic 3D stable structure made of beams of circular cross-section of radius $r$ r when the periodicity parameter $\varepsilon $ ε and the ratio ${r/\varepsilon }$ r / ε simultaneously tend to 0. The analysis is performed within the frame of linear elasticity theory and it is based on the known decomposition of the beam displacements into a beam centerline displacement, a small rotation of the cross-sections and a warping (the deformation of the cross-sections). This decomposition allows to obtain Korn type inequalities. We introduce two unfolding operators, one for the homogenization of the set of beam centerlines and another for the dimension reduction of the beams. The limit homogenized problem is still a linear elastic, second order PDE.

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