The state and partial level densities were calculated using the corresponding formulas that are obtained in the frame work of the exciton model with equidistant spacing model (ESM) and non-ESM (NESM). Different corrections have been considered, which are obtained from other nuclear principles or models. These corrections are Pauli Exclusion Principle, surface effect, pairing effect, back shift due to shell effect and bound state effect . They are combined together in a composite formula with the intention to reach the final formula. One-component system at energies less than 100 MeV and mass number range (50-200) is assumed in the present work. It was found that Williams, plus spin formula is the most effective approach to the composite formula, and it is in good agreement with experimental results. All calculation has been made using programs with MATLAB language written for this purpose.
Ericson’s formula describes the partial level density (PLD) of pre-equilibrium reactions and corrections. PLD with pairing correction can be calculated using four methods, namely, pairing, improved pairing, exact Pauli and back shift energy corrections. The variations in the PLD values of each of the four formulas of strontium (88Sr), Yttrium (89Y) and Zirconium (90Zr) isotones have been examined. Results shows that the PLD values that use pairing and improved pairing corrections do not vary for different isotones. However, a small change in PLD values is observed when exact Pauli correction and back shift energy were utilised. The change in the PLD values using back shift energy correction is bigg
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The differential cross sections of the pre - equilibrium stage are calculated at different energies using the Kalbach Systematic approach in Exciton model with Feshbach, Kerman and Koonin (FKK) statistical theory of Multistep Compound and direct reactions. In this work, the emission rate of light nuclei with emission energy in the centre of mass system in the isospin mixed case is considered in calculations to predict the cross-sections at the pre-equilibrium and equilibrium stages. The nucleons and light nuclei (2D and 3T) have been used as a projectile at the target 63Cu nuclei and at different incident energies (4MeV, 14 MeV and 14.8MeV). The comparisons between the present calculated results with other, theoretical and experimental w
... Show MoreThe pre - equilibrium and equilibrium double differential cross
sections are calculated at different energies using Kalbach Systematic
approach in terms of Exciton model with Feshbach, Kerman and
Koonin (FKK) statistical theory. The angular distribution of nucleons
and light nuclei on 27Al target nuclei, at emission energy in the center
of mass system, are considered, using the Multistep Compound
(MSC) and Multistep Direct (MSD) reactions. The two-component
exciton model with different corrections have been implemented in
calculating the particle-hole state density towards calculating the
transition rates of the possible reactions and follow up the calculation
the differential cross-sections, that include MS
The nuclear pre-equilibrium emission spectra have been studied and calculated using the exciton model with different reactions and incident energiesfor the target nuclei: . The secondary emissioncomponent has been inserted to the final emission spectrum and its effectshave been studied for only reactions with primary nucleons emission because the restrictions introduced by primary clusters emission reactions. It revealed a big contributioninenhancing the calculated energy spectra atincident energies more than
A neutron induced deuteron emission spectra and double differential cross-sections (DDX), in 27Al (n, D) 26Mg, 51V (n, D)50Ti , 54Fe ( n, D)53Mn and 63Cu (n, D) 62Ni reactions, have been investigated using the phenomenological approach model of Kalbach. The pre-equilibrium stage of the compound nucleus formation is considered the main pivot in the discription of cross-section, while the equilibrium (pick up or knock out ) process is analyzed in the framework of the statistical theory of cluster reactions, Feshbach, Kerman, and Koonin (FKK) model. To constrain the applicable parameterization as much as possible and to assess the predictive power of these models, the calculated results have been compared with the experimental data and othe
... Show More The calculated neutron yields from (α, n) reactions are very important in analyzing radiation shielding of spent fuel storage, transport and safe handling. The cross sections of 63Cu (α, n) 66Ga and 65Cu (α, n) 68Ga reactions are calculated for different α-energies using different sets of programs using Matlab language. The values deduced energy is from threshold to Eα= 30 MeV and to Eα= 40 MeV for 63Cu (α, n) 66Ga and 65Cu (α, n) 68Ga respectively. The weight average cross section was then used to calculate the neutron yields y0 (n/106α) for each reaction .The empirical formula was then suggested to calculate total neutron yield to each isotope.
The experimental proton resonance data for the reaction P+48Ti have been used to calculate and evaluate the level density by employed the Gaussian Orthogonal Ensemble, GOE version of RMT, Constant Temperature, CT and Back Shifted Fermi Gas, BSFG models at certain spin-parity and at different proton energies. The results of GOE model are found in agreement with other, while the level density calculated using the BSFG Model showed less values with spin dependence more than parity, due the limitation in the parameters (level density parameter, a, Energy shift parameter, E1and spin cut off parameter, σc). Also, in the CT Model the level density results depend mainly on two parameters (T and ground state back shift energy, E0), which are app
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There are many neutron sources in the universe that play an important role in the stellar slow neutron capture (s-process) nucleosynthesis. Fluorine-19 is a cosmically rare isotope that is generated in a series of reactions. The aim in this paper is to perform theoretical calculations to test the variance of neutron intensity generated within stellar conditions, especially in Asymptotic Giant Branch (AGB) stars, on the production of 19F isotope. EMPIRE II program has been utilized with the aid of many Matlab programs, and experimental comparisons have been made with NACRE II and Reaclib libraries. The results has shown that the high abundances of reactant nuclei responsible for ultimately generating
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In this paper the proton, neutron and matter density distributions and the corresponding root mean square (rms) radii of the ground states and the elastic magnetic electron scattering form factors and the magnetic dipole moments have been calculated for exotic nucleus of potassium isotopes K (A= 42, 43, 45, 47) based on the shell model using effective W0 interaction. The single-particle wave functions of harmonic-oscillator (HO) potential are used with the oscillator parameters b. According to this interaction, the valence nucleons are asummed to move in the d3f7 model space. The elastic magnetic electron scattering of the exotic nuclei 42K (J?T= 2- 2), 43K(J?T=3/2+ 5/2), 45K (J?T= 3/2+ 7/2) and 47K (J?T= 1/2+ 9/2) investigated t
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The ground state proton, neutron and matter densities, the corresponding rms radii and charge form factors of a dripline nuclei 6He, 11Li, 12Be and 14Be have been studied via a three–body model of (Core + n + n). The core–neutron interaction takes the form of Woods-Saxon (WS) potential. The two valence neutrons of 6He, 11Li and 12Be interact by the realistic interaction of ZBMII while those of 14Be interact via the realistic interaction of VPNP. The core and valence (halo) density distributions are described by the single-particle wave functions of the WS potential. The calculated results are discussed and compared with the experimental data. The long tail performance is clearly noticed in the calculated neutron and matter density distr
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