Measurements Of Branching Fractions In GdⅠand GdⅡ

Because the ability of human to direct contact with the outer space is still limited,our understanding of the universe mainly depends on the spectral study of extraterrestrialmaterial, so spectroscopy in the process of exploring the universe plays a very importantrole. Atomic spectroscopy provides a wealth of information on the internal structure ofatomic, the information is great significance for study of molecular structure and solidstructure. Spectrum technology is widely used in chemical astrophysical plasma physicsand some applications atomic spectrum technology promote the development of lasertechnology, in turn laser technology also provide a highly effective means forspectroscopy study. An important issue is to determine stars’ chemical composition andtheir relative abundance in astrophysics, they are the basic theory of research celestialevolution, the age of the heavenly bodies and the celestial energy sources. These studiesneed to be precise transition probabilities and oscillator strengths for the premise. Usingthe radiative lifetime and transitions branching ratios data to derive transitionprobabilities and oscillator strength is one of the most common and most reliablemethod.In this paper, branching fractions of gadolinium atom and ion are analyzed basedon the above theory. Using the high resolution grating monochrome andphoto-multiple，we have measured branching fractions of7levels from the4f75d26p，4f85d6s,4f86s6p and4f86s7s configuration of Gd I and6levels from4f75d6pconfiguration of Gd II through analyzing the whole emission spectrum of agadolinium hollow cathode lamp. Also, oscillator strengths and absolute transitionprobabilities for the related13levels have been inferred from a combination of theradiative lifetimes measured by others.To check up the accuracy of the experimental data, the comparison between our values and other results show excellent agreement. Furthermore, we seriously analyzethe reason of the experimental error and give the range of the error.The results of this paper enriches the atomic and ionic spectral data, help people tobe closer study of the atomic structure of gadolinium and for astrophysics, plasmaphysics and related disciplines have important reference value.