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Light Charged Particles Induced Nuclear Reactions on Some Medium Weight Nuclei for Practical Applications

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Light Charged Particles Induced Nuclear Reactions on Some Medium Weight Nuclei for Practical Applications Ain Shams University Faculty of Science Physics Department Light Charged Particles Induced Nuclear Reactions on some Medium Weight Nuclei for Practical Applications Thesis Submitted for the Partial Fulfillment of Master Degree in Physics (Nuclear Physics) By Bahaa Mohamed Ali Mohamed Mohsena BSc. in Physics 2004 To Physics Department- Faculty of Science Ain Shams University Egypt 2011 Ain Shams University Faculty of Science Physics Department Light Charged Particles Induced Nuclear Reactions on some Medium Weight Nuclei for Practical Applications Thesis Submitted for the Partial Fulfillment of Master Degree in Physics (Nuclear Physics) By Bahaa Mohamed Ali Mohamed Mohsena BSc. in Physics 2004 Supervised by Prof.Dr. Samir Yousha El Kameesy Prof. of Nuclear Physics Physics Department Faculty of Science Ain Shams University Prof.Dr. Usama Seddik Abd Alghafar Prof. of Nuclear and Particle Physics Physics Department Nuclear Research Center Atomic Energy Authority Dr. Mogahed Ibrahim Al Abyad Lecturer of Nuclear Physics Physics Department Nuclear Research Center Atomic Energy Authority Ain Shams University Faculty of Science Physics Department Approval Sheet Light Charged Particles Induced Nuclear Reactions on some Medium Weight Nuclei for Practical Applications Name of Candidate Bahaa Mohamed Ali Mohamed Mohsena Supervised by Signature Prof.Dr. Samir Yousha El Kameesy Prof.Dr. Usama Seddik Abd Alghafar Dr. Mogahed Ibrahim Al Abyad Acknowledgment ACKNOWLEDGMENT All thanks go first to ALLAH. I would like to thank Prof. Dr. Samir El-Kameesy for his kindness, support, continuous encouragement and guidance during this study. I would like to thank deeply Prof. Dr. Usama Seddik for his scientific supervision and kind help for me from my first day in the AEA cyclotron project. He showed steady interest and provided constant guidance and encouragement during this study. I would like to give special great thanks to my supervisor Dr. Mogahed Al-Abyad for suggesting the subject of this thesis. His scientific supervision, guidance, support, encouragement and contribution in the experimental work are highly appreciated. I am highly indebted to him for his investigations and carrying out the theoretical nuclear reaction model calculations. I would like to thank Dr. Ditrói, Institute of Nuclear Research of the Hungarian Academy of Science, ATOMKI, Debrecen, Hungary for establishing this work in his laboratory. My great thanks go also for Prof. Dr. Tárkányi and Dr. Takács. I wish to express my great thanks for both cyclotron crews in Inshas Egypt and Debrecen Hungary. This work would have not been possible without the efforts of them. My special thanks go to my father, mother and wife. Bahaa Mohamed Ali Cairo, 2011 I Abstract ABSTRACT The radioisotopes of indium, cadmium and tin have many practical and medical applications. Their standard routes for production are proton or deuteron induced reactions on natural or enriched cadmium or tin. The production via 3He induced reactions on natural or enriched cadmium was rarely discussed. In this study 3He induced reactions on natural cadmium were measured utilizing the stacked-foil technique. The primary incident beam energy was 27 MeV extracted from the MGC-20E cyclotron, Debrecen, Hungary. The excitation functions for the reactions natCd(3He,x)115g,111mCd, 117m,g,116m,115m,114m,113m,111g,110m,g,109g,108g,107gIn and 117m,113g,111,110Sn were evaluated. The data were compared with the available literature data. Different theoretical nuclear reaction models were also used to predict the cross sections for those reactions. The used models were ALICE-IPPE, TALYS-1.2 and EMPIRE-03. The experimental data were compared also to the theoretical model calculations. The theoretical models did not describe most of the experimental results. The isomeric cross section ratios for the isomeric pairs 117m,gIn and 110m,gIn were calculated. The isomeric cross section ratio depends on the spins of the states of the interested isomeric pair. The calculated isomeric ratios helped to identify the mechanisms of the reactions involved. The integral yields for some medically relevant isotopes were calculated using the excitation function curves. II Contents CONTENTS TITLE Page ACKNOWLEDGEMENT I ABSTRACT II CONTENTS III LIST OF FIGURES VI LIST OF TABLES VIII SUMMARY X CHAPTER 1: INTRODUCTION AND LITRATURE REVIEW 1.1. RADIOACTIVITY 1 1.2. ISOTOPES 2 1.2.1. PRODUCTION OF ISOTOPES 2 1.2.2. APPLICATION OF RADIOISOTOPES 3 1.3. FUNDAMENTALS OF NUCLEAR REACTIONS 5 1.3.1. NUCLEAR REACTION ENERGETIC 7 1.3.2. REACTION THRESHOLD ENERGIES 8 1.3.3. REACTION CROSS SECTION 10 1.3.3.1. CROSS SECTION MEASUREMENT 12 1.3.3.2. TARGET YIELD 15 1.3.4. REACTION CHANNELS 17 1.3.5. STOPPING POWER AND RANGE 17 1.3.6. NUCLEAR REACTION MECHANISMS 22 1.3.6.1. COMPOUND NUCLEAR REACTIONS 23 1.3.6.2. DIRECT REACTIONS 25 1.3.6.3. PRECOMPOUND REACTIONS 26 27 1.4. BASICS OF GAMMA RAY DETECTORS 1.4.1. SCINTILLATION DETECTORS 28 1.4.2. SEMICONDUCTOR DETECTOR 29 1.4.3. THE DETECTOR EFFICIENCY 32 1.4.3.1. ABSOLUTE EFFICIENCY 32 III Contents 1.4.3.2. INTRINSIC EFFICIENCY 33 1.4.3.3. RELATIVE EFFICIENCY 33 1.5. LITERATURE REVIEW 34 1.6. AIM OF THE WORK 35 CHAPTER 2: APPARATUS AND EXPERIMENTAL TECHNIQUES 2.1. THE CLASSICAL CYCLOTRON 38 2.2. THE AVF CYCLOTRON 41 2.3. IRRADIATION BY MGC-20 CYCLOTRON 41 2.3.1. MAGNET 43 2.3.2. ACCELERATING CHAMPER 44 2.3.3. RESONANCE SYSTEM 44 2.3.4. ION SOURCE 45 2.3.5. GAS SUPPLY SYSTEM OF THE ION SOURCE 46 2.3.6. VACUUM SYSTEM 46 2.3.7. WATER COOLING SYSTEM 46 2.3.8. BEAM EXTRACTION SYSTEM 47 2.3.9. BEAM MONITORING AND DIAGNOSTICS 47 2.3.10. BEAM TRANSPORT SYSTEM 48 3 2.4. IRRADIATION BY He 49 2.5. STACKED-FOIL TECHNIQUE 50 2.6. TARGET PREPARATION 51 2.7. ACTIVITY MEASUREMENT 54 CHAPTER 3: THEORETICAL CALCULATIONS 3.1. ALICE-IPPE 58 3.2. TALYS-1.2 60 3.3. EMPIRE-03 (ARCOLA) 65 CHAPTER 4: RESULTS AND DISCUSSION 4.1. EXCITATION FUNCTIONS OF TIN ISOTOPES 76 117m 4.1.1. FORMATION OF Sn 76 113g 4.1.2. FORMATION OF Sn 78 111 4.1.3. FORMATION OF Sn 80 IV Contents 110 4.1.4. FORMATION OF Sn 82 4.2. EXCITATION FUNCTIONS OF INDIUM 83 ISOTOPES 117m,g 4.2.1. FORMATION OF In 83 116m 4.2.2. FORMATION OF In 86 115m 4.2.3. FORMATION OF In 87 114m 4.2.4. FORMATION OF In 89 113m 4.2.5. FORMATION OF In 90 111g 4.2.6. FORMATION OF In 92 110m,g 4.2.7. FORMATION OF In 93 109g 4.2.8. FORMATION OF In 96 108g 4.2.9. FORMATION OF In 98 107g 4.2.10. FORMATION OF In 99 4.3. EXCITATION FUNCTIONS OF CADMIUM 101 ISOTOPES 115g 4.3.1. FORMATION OF Cd 101 111m 4.3.2. FORMATION OF Cd 102 4.4. ISOMERIC CROSS SECTION RATIOS 104 117m,g 4.4.1. ISOMERIC CROSS SECTION RATIO OF In 104 110m,g 4.4.2. ISOMERIC CROSS SECTION RATIO OF In 106 4.5. YIELD CALCULATIONS 108 CONCLUSION 112 REFERENCES 114 ARABIC SUMMARY XI V List of Figures LIST OF FIGURES Figure Page number Caption Fig. 1.1 Growth of daughter activity A(t) normalized to 16 saturation activity Asat plotted against time normalized to the half-life of the daughter (t1/2). The slope of the tangent on the A(t)/(Asat) vs. t curve at t = 0, defined as the activation yield (Y), is also shown. Fig. 1.2 Collisions of charged particle with an atom, depending 18 on the relative sizes of the impact parameter b and atomic radius a. Fig. 1.3 The shape of the collision stopping power curve as a 21 function of the charged particle kinetic energy E. Fig. 1.4 Formation nuclear reaction of the compound nucleus 24 51Cr through various entrance channels and decay through various exit channels. Fig. 1.5 At higher energies, it’s more likely that additional 25 neutrons will evaporate from the compound nucleus. Fig. 1.6 Schematic energy spectrum of particles emitted at a 27 given angle and for a specific residual nucleus as a consequence of a nuclear reaction. The dashed curve represents the compound nuclear contribution. The discrete peaks at the high energy end correspond to direct reaction contribution. Fig. 1.7 Schematic diagram of a scintillation counter. 29 Fig. 1.8 Comparison of NaI(Tl) and HPGe spectra for 99mTc. 30 Fig. 1.9 A symple schematic electronic system for gamma 31 spectrometry. Fig. 2.1 Schematic diagram of a classical cyclotron. 39 Fig. 2.2 Magnetic pole of AVF cyclotron with and without spiral 41 angels. Fig. 2.3 Schematic diagram of the MGC-20 cyclotron. 43 Fig. 2.4 The Hungarian MGC-20E cyclotron. 44 Fig. 2.5 Proton beam profile. 48 Fig. 2.6 Hungarian beam transport Line. 49 Fig. 2.7 Schematic arrangement for target and monitor stacked- 51 foils. VI List of Figures Fig. 2.8 Cross section of a typical HPGe detector. 54 Fig. 2.9 Live photo of the HPGe detector and the system of data 55 acquisition. Fig. 2.10 The efficiency curve of the detector at 12 cm source to 56 detector distance. Fig. 3.1 Flowchart of TALYS code. 64 Fig. 3.2 Flowchart of EMPIRE code. 68 Fig. 4.1 Excitation function of the monitor reaction 73 natTi(3He,x)48V. Fig. 4.2 Excitation function of 116Cd(3He,2n)117mSn reaction. 78 Fig. 4.3 Excitation function of the natCd(3He,xn)113Sn reaction. 80 Fig. 4.4 Excitation function of the natCd(3He,xn)111Sn reaction.
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