The Pre-equilibrium spectrum emission for nucleon-nucleon reaction using the non- equidistant spacing feshbach-kerman-koonin (FKK)‎ model of some heavy nuclei

Other Title(s)

الطيف المنبعث قبل التوازن لتفاعل نيوكليون-نيوكليون باستخدام أنموذج فيشباخ-كيرمان-كونن اللامتساوي الأبعاد لبعض الأنوية الثقيلة

Dissertant

Ahmad, Rasha Subayh

Thesis advisor

Dakhil, Zahidah Ahmad
Jasim, Mahdi Hadi

Comitee Members

Mansur, Hazim Luwis
Radi, Rad Abd al-Karim
Shafiq, Shafiq Shakir
Adib, Nadiyah Muhammad
Abbud, Sad Naji

University

University of Baghdad

Faculty

College of Science

Department

Department of Physics

University Country

Iraq

Degree

Ph.D.

Degree Date

2013

English Abstract

The pre-equilibrium exciton model with extending the formalism to include the MSD and MSC parts of FKK- model has been used in the present work.

Using this model, an empirical formula has been introduced to calculate the level density parameter, which has a significant effect upon the state density.

The calculations have been performed and tabulated in APPENDIX A, for 106 odd-odd, even-even, and odd mass nuclei, in case of 18< z <108.

The effect of the nuclear excitation energy on the disposal of energy levels has been studied by calculating the level spacing.

Due to the impact of the nuclear excitation energy on the energy levels, and the convergence of each other with increasing the excitation energy, the non-Equidistant Spacing Model (non ESM) has been adopted in the present work, where the effect of the single particle and single hole excitation energy has been supplemented in the state density formula.

The Pauli, surface, pairing, parity, the back shift, the angular momentum, isospin, the bound state and the finite depth corrections, have been added to the state density formula, and collected in ??correction function.

The effect of adding each individual correction at the disposal of this function has been studied.

The effect of the isospin has been examined for the cases: ? = ??, ? = ?? + 1, and ? = ?? + 2, in the two-component system and for different exciton numbers.

It is concluded that the effect of isospin is clear at high excitation energies.

After including all the required corrections, a composite state density formula has been adopted in the present work to estimate the transition rates and then the spectrum.

The required binding energies are calculated and tabulated in APPENDIX B, for primary emissions: (n, n), (n, p), (n, D), (n, T), (n, 3He), (n, 4He), (p, n), (p, p), (p, D), (p, T), (p, 3He) and (p, 4He), for ???? ?? , ?ℎ ?? ??? and ?? ?? ??? .

In addition, the binding energies for secondary emitted particles like (p, n, D, T, 3He, 4He) have also been estimated.

The differential and the double differential cross sections are studied, for ???? ?? and for deformed nuclei, ???ℎ ??? and ?? ?? ??? , at emission energies up to 30 MeV.

The knockout, IX the Multi Step Direct (MSD) and Multi Step Compound (MSC) emissions are included into the spectrum calculations.

The present results are compared with other experimental data (EXFOR), and theoretical published results, BROND, ENDF, JEFF, JENDL, and the most recent one TENDLE-2011.

All calculations were performed using the high-level technical computing language (MATLAB).

The results of the calculated spectrum in the present work are compared with other practical data and theoretical results, these comparisons give a good agreement using un deformed nuclei, such as ???? ?? .

The deformation effect seems clear in the low-lying emission energy yields from strong spectroscopic collective states in ???ℎ ??? and ?? ?? ??? , and this reflects on the spectrum results.

Main Subjects

Physics

No. of Pages

126

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-608058