Theoretical Calculation On Isotope Shifts Of N I

Isotope shifts?ISs?play an important role in the research of nuclear properties and atomic hyperfine structure,and be widely used in the fields of astrophysics,nuclear physics,and cold atomic physics.Atomic nitrogen?N I?is of great relevance in many chemical and physical processes,for instance,plasma physics,astrophysics,atmospheric physics,and combustion kinetics.In this work,the isotope shifts of atomic nitrogen were studied by using MCDHF and RCI methods.In the calculation process,we systematically considered the electronic correlation effect and the relativistic effect,and introduced the Breit approximation into the RCI calculation.The special mass shift parameters and the field shift parameters of 17 transition lines of nitrogen were calculated by GRASP2K and RIS3 packages.The special mass shifts,normal mass shifts,field shifts and isotope shift values of four multiples?3s⁴P?3p⁴P°,3s⁴P?3p⁴D°,3s²D?5p²D°and3s²P?3p²P°?of ¹⁴N and ¹⁵N were also obtained.In addition,the calculated values in this work were compared with other reported theoretical and experimental results.The relationship between isotope shifts and J values were discussed and analyzed in this work.This thesis also introduced the progress of LabVIEW program in the measurement experiment of atomic and molecular spectroscopy.We have realized the simultaneous signal acquisition of wavemeter,photon counter,and sub-Doppler absorption spectra of gaseous iodine molecules.