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(Si) Core-Silica Shell Nano-Wires Analysis of Δ0(1232) Production in p+12C and d+12C Collisions at 4.2 GeV/c Per Nucleon By Imran Khan CIIT/FA10-PPH-002/ISB PhD Thesis In Physics COMSATS Institute of Information Technology Islamabad-Pakistan Spring 2013 COMSATS Institute of Information Technology Analysis of Δ0(1232) Production in p+12C and d+12C Collisions at 4.2 GeV/c Per Nucleon A Thesis Presented to COMSATS Institute of Information Technology, Islamabad In partial fulfillment Of the requirement for the degree of PhD Physics By Imran Khan CIIT/FA10-PPH-002/ISB Spring, 2013 ii Analysis of Δ0(1232) Production in p+12C and d+12C Collisions at 4.2 GeV/c Per Nucleon A Post Graduate Thesis submitted to the Department of Physics as partial fulfillment of the requirement for the award of Degree of PhD (Physics) Name Registration Number Imran Khan CIIT/FA10-PPH-002/ISB Supervisor Dr. Khusniddin Olimov HEC Foreign Professor Department of Physics COMSATS Institute of Information Technology, Islamabad Co-Supervisor Dr. Mahnaz Q. Haseeb Professor Department of Physics COMSATS Institute of Information Technology, Islamabad iii Final Approval This thesis titled Analysis of Δ0(1232) Production in p+12C and d+12C Collisions at 4.2 GeV/c Per Nucleon By Imran Khan CIIT/FA10-PPH-002/ISB Has been approved For the COMSATS Institute of Information Technology, Islamabad External Examiner: ________________________________________________ Dr. Mahmood-Ul-Hassan Department of Physics, University of Punjab, Lahore External Examiner: ________________________________________________ Prof. Dr. Fayyazuddin National Center for Physics, Quaid-i-Azam University, Islamabad Supervisor: ______________________________________________________ Dr. Khusniddin Olimov HEC Foreign Professor, Department of Physics COMSATS Institute of Information Technology, Islamabad HoD: ___________________________________________________________ Prof. Dr. Arshad Saleem Bhatti Head of Department of Physics COMSATS Institute of Information Technology, Islamabad Chairman: _______________________________________________________ Prof. Dr. Sajid Qamar Chairman, Department of Physics COMSATS Institute of Information Technology, Islamabad Dean, Faculty of Sciences: __________________________________________ Prof. Dr. Arshad Saleem Bhatti Dean, Faculty of Sciences COMSATS Institute of Information Technology, Islamabad iv Declaration I Imran Khan, registration Number CIIT/FA10-PPH-002/ISB, hereby declare that I have produced the work presented in this thesis, during the scheduled period of study. I also declare that I have not taken any material from any source except referred to wherever due that amount of plagiarism is within acceptable range. If a violation of HEC rules on research has occurred in this thesis, I shall be liable to punishable action under the plagiarism rules of the HEC. Date: _______________ Signature of the Student:__________________ Imran Khan CIIT/FA10-PPH-002/ISB v Certificate It is certified that Imran Khan, registration Number CIIT/FA10-PPH-002/ISB, has carried out all the work related to this thesis under my supervision at the Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad and the work fulfills the requirement for award of PhD degree. Date: ________________ Supervisor: ____________________ Dr. Khusniddin Olimov HEC Foreign Professor Department of Physics COMSATS Institute of Information Technology, Islamabad Head of Department: __________________ Prof. Dr. Arshad Saleem Bhatti Head of Department of Physics, COMSATS Institute of Information Technology, Islamabad vi Dedicated To My Family … Abbu, Amee, Shakeel, Idrees, Tufail, Adnan And Pyari Behna ... They do their best for me… vii ACKNOWLEDGEMENTS All of my praises are running towards the Almighty ALLAH, the most Merciful and the most Beneficent. He blessed me the opportunity to take admission in PhD in the field of High Energy Physics and gave me enough strength and patience to complete it. I feel pleasure to express my deep and sincere thanks to my supervisor, HEC Foreign Professor, Dr. Khusniddin Olimov from Department of Physics, COMSATS Institute of Information Technology, Islamabad, for his best guidance, continual help, and encouragement throughout the course of this research work. Without his careful attention and encouragement, this thesis would have never been completed. I am also very grateful to my co-supervisor Professor Dr. Mahnaz Q. Haseeb, Department of Physics, COMSATS Institute of Information Technology, Islamabad, for her tremendous help, valuable suggestions and affectionate guidance. I wish to extend my sincere gratitude to Prof. Dr. Sajid Qamar, Chairman, Department of Physics, to Prof. Dr. Arshad Saleem Bhatti, HoD of Physics and Dean, Faculty of Sciences, and to Dr. S. M. Junaid Zaidi, Rector, COMSATS Institute of Information Technology, Islamabad, for providing me all the required facilities to complete my PhD studies and research in Physics at COMSATS Institute of Information Technology, Islamabad. I also wish to thank the staff and colleagues from the Department of Physics, COMSATS Institute of Information Technology, Islamabad, for their moral and practical help throughout this research work. I would like to give my special thanks to Prof. Dr. Mais Suleymanov, Dr. Ijaz Ahmad, and PhD students Ali Zaman and Akhtar Iqbal for their various support and encouragement. I am also very thankful to the Higher Education Commission (HEC), Islamabad, for providing me the financial support under the “Indigenous MS Leading to PhD 5000 Scholarships Program” during the whole period of my studies. Without HEC assistance it would not be possible for me to continue my studies after getting M. Sc. in Physics. viii I am very grateful to my friend Aamir Sohail Mughal and his family for their full cooperation during my MS and PhD studies. His sincere friendship has made it easier for me to complete my studies. I have no words to pay thanks to my family members. How can I thank my Father, my Mother, and my Grand Father for their countless prayers and lots of hardships they suffered during my studies? My head is bowed before their sacrifices. I am very grateful to my dear brothers Muhammad Shakeel Ahmad, Muhammad Idrees Khan, Muhammad Tufail Khan, Muhammad Adnan Khan, my Sweet Sister and Uncle Muhammad Younas, and Muhammad Ismail for their full support during my studies. I thank all my relatives, especially Zahid, Zubair, Israr, Daniyal, and friends: especially Liaqat Ali Khan, Muhammad Sameen, Khalil-ur-Rahman, Zahir Ahmad, Muhammad Sadeeq, Khalil Ahmad, and Rafi Ullah for their best wishes for me. Imran Khan ix ABSTRACT Analysis of Δ0(1232) Production in p+12C and d+12C Collisions at 4.2 GeV/c Per Nucleon Production and various properties of Δ0(1232) resonances in p+12C and d+12C collisions at a momentum of 4.2 GeV/c per nucleon were analyzed. The mass distributions of 0 (1232)'s in both collision types were reconstructed by analyzing the experimental and background invariant mass distributions of proton and negative pion pairs with the help of angular criterion. The emission angle, rapidity, momentum, transverse momentum, and kinetic energy distributions of were reconstructed for both collision types and their mean values extracted. Analyzing the reconstructed transverse mass spectra of , the freeze-out temperatures of were estimated for both collision types. The parameters and various characteristics of Δ0(1232) resonances produced in p+12C and d+12C collisions at the same incident momentum per nucleon were compared with each other to get the valuable information about the role of the weakly bound neutrons of projectile deuterons in Δ0(1232) production. The spectral temperatures of produced in p+12C and d+12C interactions at 4.2 GeV/c per nucleon were extracted by analyzing the transverse momentum spectra of in the framework of Hagedorn Thermodynamic Model and compared with the corresponding temperatures of negative pions in p+12C and d+12C collisions. x TABLE OF CONTENTS 1 Introduction 1 1.1 Introduction 2 1.2 Properties of Δ(1232) resonances 4 1.3 Aims and outline of the thesis 5 2 Experimental Procedures and Models 8 2.1 The Synchrophasotron and Accelerators complex of JINR 9 2.2 Bubble Chamber 15 2.3 Experiment 19 2.4 Modified FRITIOF Model 22 2.5 Quark-Gluon-String Model 26 2.6 Dubna Cascade Model 29 3 Reconstruction of Mass Distributions of Δ0(1232) Resonances 32 3.1 Momentum distributions and mean multiplicities of protons and pions 33 3.2 The Method 36 3.3 Dependence of obtained parameters on cutoff parameter ε 41 3.4 Mass distributions of Δ0(1232) resonances 44 3.5 Fractions of negative pions coming from Δ0(1232) decay 47 3.6 Relative numbers of nucleons excited to 0(1232) at freeze- out conditions 51 4 Comparison of Kinematical Spectra of Δ0(1232) in p+12C and d+12C Collisions 54 4.1 Reconstruction of kinematical spectra of Δ0(1232) 55 4.1.1 Momentum, Transverse Momentum, Kinetic Energy, and Emission Angle distributions of Δ0(1232) resonances 56 xi 4.2 Rapidity distributions of Δ0(1232) resonances 62 5 Temperatures of Δ0(1232) Resonances 70 0 12 5.1 Spectra of Invariant Cross Sections of Δ (1232) in p+ C and d+12C collisions 71 0 5.2 Estimation of the freeze-out temperatures of Δ (1232) from analysis of reconstructed invariant transverse mass spectra 73 0 5.3 Extraction of the spectral temperatures of Δ (1232) within the framework of Hagedorn Thermodynamic Model 89 0 5.4 Comparison of spectral temperatures of Δ (1232) and negative pions in p+12C and d+12C collisions 92 6 Summary and Conclusions
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