الفهرس 
Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
In the present work the effects of isomeric state formation on the measurement of thermal neutron cross section (σo) and its associated resonance integral (Io) on neutrons reaction are discussed. In this aspect we distinguish between the use of isomeric state capture cross section and the whole nucleus’s formation cross section.
The investigation had covered the isomeric thermal neutron cross section and isomeric resonance integral of 109Ag(n,γ)110mAg, 133Cs(n,γ)134mCs, 134gCs,136Ba(n,γ)137mBa, 68Zn (n,γ)69mZn, 79Br(n,γ)80m+gBr and 81Br(n,γ)82m+gBr together with validation of the values of 115In(n,γ)116mIn monitor reaction cross section and resonance integral.
These reactions are sensitive to the neutron energy distribution. For this purpose, a well moderated and stable neutron flux neutron source was used to overcome the problems of fluctuations in spatial or temporal flux distribution and imitate deviance of the measured values of cross section and resonance integral.
These residual nuclei have broad half-life time scale (isomeric states having different half-life time from 2.5 min to 2 year). We solved the problem of the diverse half-life value of the residual nuclei by considering the highly stable neutron irradiation facility.
Two identical isotopic neutron sources made of 241Am-9Be were used in our irradiation setup together with specially-designed sample holder made of polypropylene to ensure full moderation and homogenization of the neutron flux distribution within the irradiation position.
Model calculations were performed using EMPIRE 3.22 code for nuclear reactions calculations. With the present steady irradiation setup, values of σx,o and Ix,o for the long-lived 110mAg isomeric state, and 134gCs ground state as well as moderately-lived 134mCs, 69mZn, 80m+gBr and 82m+gBr isomers and the short-lived 137mBa residual nucleus were determined, our setup using in steady moderated neutron flux.
Confirmation of accuracy was done using the k0-factor of the well-known monitor reaction of neutron with indium. k0-factor was measured for first time for 137mBa.
The thesis consists of four chapters in addition to this summary and conclusions.
Chapter 1: Introduction and Literature Review
This chapter contains introductory notes and literature review concerning neutron reactions; level structure and neutron activation analysis.
The aim of the present work and the actions used to achieve our goal are also mentioned.
Chapter 2: Theoretical Background
This chapter gives the meaning of nuclear cross section, and nuclear models are given, such as:
• Statistical model
• Optical model
• Shell model
The level density was discussed and its calculation by different models by EMPIRE code.
Chapter 3: Experimental Work
This chapter begins with discussing the factors which used for cross section calculation and resonance integral, such as:
• Reaction rate from experimental results are also given.
• Self- shielding factor.
• Cadmium transmission factor.
• Flux calculation.
Also the uncertainty was calculated for thermal cross section and resonance integral.
The samples were characterization which used, and the neutron source 241Am-Be source. Also included a description for single γ-ray spectrometer:
• In neutron lab (Egyptian atomic energy Authority).
• In nuclear physics lab (physics department, Dr. Hussein Abu Leila lab), faculty of women for arts, science and education.
Chapter 4: Results and Discussions
This chapter contains the result of reaction rate for irradiated samples and monitors with and without cd. the discussion of the experimental results of the isomeric thermal cross section and resonance integral for 109Ag (n, γ) 110mAg, 133Cs (n, γ) 134mCs and 134gCs, 136Ba (n, γ) 137mBa, 68Zn (n,γ)69mZn, 79Br(n,γ)80m+gBr and 81Br(n,γ)82m+gBr reactions.
Also this chapter contain theoretical model calculations are given and discussed in details