Study On The Neutron And ? Induced Reactions On Intermediate Mass Nuclei By Optical Model

Neutron induced reaction can be applied to doping of organic materials.Gamma induced reaction is also widely applied in biology and medicine.In this thesis,we use the optical model to study the neutron and gamma induced nuclear reactions,adopted by the TALYS1.4 toolkit.In this paper,all theoretical data for nuclear reaction are calculated by TALYS toolkit.The main content is divided into three parts:?1?The neutron induced reactions on stable Carbon,Nitrogen,and Oxygen isotopes are investigated by using the Talys1.4 toolkit with the default parameters.The neutron incident energy covers a range from0.20 MeV to 85.00 Me V.For ¹²C and ¹⁴N,the Talys1.4 results agree with the experimental data,while the parameters should be adjusted for ¹⁶O.Some En windows are found by comparing the main channels of n +C/N/O reactions.In these En windows,a specific element is activated to a different one while leaving the other element atoms unchanged.The results will facilitate the research of doping effects in organic materials by using neutron activation technique.?2?The neutron induced reactions on ²⁷Al and ¹⁹F nuclei are investigated by using the Talys1.4 toolkit with the default parameters.Incident neutron energies in a wide range from 0.10 keV to 30.00 MeV are calculated.The cross sections for the main channels?n,np?,?n,p?,?n,??,?n,2n?,?n,??and the total reaction cross section?n,tot?of the reactions are obtained.Except that the ¹⁹F nucleus is in the intermediate zone between the region of validity of statistical theory and the region of light nuclei that require detailed treatment.Based on the calculations for the n + ²⁷Al and n + ¹⁹F reactions,the results of the n + ²⁷Al¹⁹F reactions are predicted.These results are useful both for the design of thorium-based molten salt reactors and for neutron activation analysis techniques.?3?An investigation on ? induced activation reactions on human essential elements.In radiotherapy,the energy of the ? rays used could be larger than 10.00 MeV,which would potentially activate the stable nucleus into a radioactive one.The ? induced reactions on some of the human essential elements are studied to show the probability of changes of nuclei.The reactions investigated include the??,n?and??,p?channels for the stable Na,Mg,Cl,Ca,Fe and Zn isotopes,with the ? incident energy of ranging from 1 to30.00 MeV.It was found that the cross sections for the reactions are very low,and the maximum crosssection is no larger than 100.00 mb.By considering the threshold energy of the channel,the half-life time of the residue nucleus,and the percentage of the element accounting for the weight and its importance in the body,it is suggested to track the radioactive nuclei ²²Na,⁴¹Ca,^42,43K and ⁵⁵Fe after therapy.The results might be useful for medical diagnosis and disease treatment.