Statistical model calculations for evaporation residue and fission cross sections in210Po compound nucleus.

The 7Li + 11 Β reaction has been studied in the energy range from a little below to about three times the Coulomb barrier by measuring the cross section of the 7- ray transitions in the residual nuclei produced. Statistical compound nucleus calculations have been performed in order to interpret the experimental data as well as to extract cross sections of the individual exit channels. The statistical compound nucleus theory can reproduce rather well the absolute j - ray and the various reaction channel excitation functions.

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Statistical model calculations of 72,73Ge(n,p) and 72,74Ge(n,α) reactions on natural Ge

HNPS Proceedings ◽

10.12681/hnps.2626 ◽

2020 ◽

Vol 15 ◽

pp. 104

Author(s):

S. Galanopoulos ◽

R. Vlastou ◽

P. Demetriou ◽

M. Kokkoris ◽

C. T. Papadopoulos ◽

...

Keyword(s):

Statistical Model ◽

Energy Range ◽

Neutron Energy ◽

Cross Sections ◽

Reaction Cross ◽

Model Calculations ◽

Monoenergetic Neutron ◽

Theoretical Investigations ◽

Equilibrium Emission ◽

Reaction Cross Sections

Systematic experimental and theoretical investigations of the 72,73Ge(n,p)72,73 Ga and 72,74Ge(n,α)69,71Znm reaction cross sections are presented in the energy range from thresh- old to about 17 MeV neutron energy. The above reaction cross sections were measured from 8.8 to 11.4 MeV by using the activation method, relative to the 27Al(n,α)24Na refer- ence reaction. The quasi-monoenergetic neutron beams were produced via the 2H(d,n)3He reaction at the 5 MV VdG Tandem T11/25 accelerator of NCSR “Demokritos”. Statisti- cal model calculations using the code EMPIRE-II (version 2.19) taking into consideration pre-equilibrium emission were performed on the data measured in this work as well as on data reported in literature.

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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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COLD FUSION REACTIONS USING NEUTRON-RICH PROJECTILES

International Journal of Modern Physics E ◽

10.1142/s0218301313500614 ◽

2013 ◽

Vol 22 (08) ◽

pp. 1350061 ◽

Cited By ~ 2

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).

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Thermonuclear Reaction Rates for Reactions Leading to N = 28 Nuclei

Australian Journal of Physics ◽

10.1071/ph950125 ◽

1995 ◽

Vol 48 (1) ◽

pp. 125

Author(s):

A.J Morton ◽

DG Sargood

Keyword(s):

Statistical Model ◽

Nuclear Reaction ◽

Cross Sections ◽

Optical Model ◽

Reaction Rates ◽

Reaction Cross ◽

Model Parameters ◽

Thermonuclear Reaction ◽

Model Calculations ◽

Reaction Cross Sections

Nuclear reaction cross sections derived from statistical-model calculations have been used in the calculation of thermonuclear reaction rates for 36 nuclei at temperatures that are representative of the interiors of evolving stars and supernovae as nucleosynthesis approaches the production of nuclei with N = 28. The statistical-model calculations used optical-model parameters in the particle channels which had been selected to give the best overall agreement between theoretical and experimental cross sections for reactions on stable target nuclei in the mass and energy ranges of importance for the stellar conditions of interest. The optical-model parameters used, and the stellar reaction rates obtained, are tabulated. Comparisons are made between these stellar rates and those from other statistical-model calculations in the literature.

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Isomeric cross section study of neutron induced reactions on Ge isotopes

EPJ Web of Conferences ◽

10.1051/epjconf/202023901028 ◽

2020 ◽

Vol 239 ◽

pp. 01028

Author(s):

R. Vlastou ◽

A. Kalamara ◽

G. Gkatis ◽

A. Stamatopoulos ◽

M. Kokkoris ◽

...

Keyword(s):

Statistical Model ◽

Cross Section ◽

Cross Sections ◽

Residual Nucleus ◽

Activation Technique ◽

Flux Variation ◽

Model Calculations ◽

Neutron Beams ◽

Hpge Detectors ◽

Empire Code

Cross sections for the 70,76Ge(n,2n), 72,73Ge(n,p) and 72,74Ge(n, α) reactions have been measured at the 5.5 MV tandem T11/25 Accelerator Laboratory of NCSR Demokritos, using the activation technique. Neutron beams have been produced in the ~16-20 MeV energy region, by means of the 3H(d,n)4He reaction. The maximum flux has been determined to be of the order of 105 n/cm2 s, while the flux variation of the neutron beam was monitored by using a BF3 detector. The cross section has been deduced with respect to the 27Al(n, α)24Na and 93Nb(n,2n)92mNb reference reactions. The contaminations from reactions induced on neighboring Ge isotopes and leading to the same residual nucleus, have been taken into account. After the end of the irradiations, the activity induced by the neutron beams at the targets and reference foils, has been measured by HPGe detectors. Statistical model calculations using the EMPIRE code were performed on the data measured in this work as well as on data reported in literature.

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