The Optical Characteristics of Hollow Cathode Discharge Striations in Nitrogen
HE Shou-jie1, HA Jing2, GUO Shu-qing1, LIU Zhi-qiang1, DONG Li-fang1
1. College of Physics Science and Technology, Hebei University, Baoding 071002, China 2. College of Science, Agricultural University of Hebei, Baoding 071001, China
Abstract：The characteristics of striations in cylindrical hollow cathode discharge were investigated experimentally. The spectra of striations were measured at a pressure of 20 Pa in a discharge of 1.3 mA, in which the main spectra are the emission spectrum lines of the N2 first positive band(B3Пg→A3Пu)and second positive band system (C3Пu→B3Пg). The spatial characteristics of vibrational temperature of N2 were calculated based on the theory of double molecular spectrum. It is shown that the emission intensity exhibits a periodic structure with an unequal magnitude, and the spectral intensity of bright striation is higher than that of dark striations. The vibrational temperature of bright striation is of the value of 3500-4400K, moreover the vibrational temperature in the bright regions decreases from the cathode to the anode. In addition, the characteristics of striations at 1.0 mA and 1.5 mA were obtained, and the influence of discharge current on the striations was investigated. It is shown that the vibrational temperature and the distance between two striations increase. Finally the reduced electric field was calculated, which is about 44～49 m-1·Pa-1, moreover it decreases with the increase in discharge current. The results are very useful for understanding the mechanism of discharge striations and for improving the stability of hollow cathode discharge.
Key words：Hollow cathode discharge;Striation;Emission spectra;Molecular vibrational temperature
[1] Raizer Y P. Gas Discharge Physics. Berlin Heidelberg: Springer-Verlag, 1991. [2] Kolobov V I, Arslanbekov R R. IEEE Trans. Plasma Sci., 2006, 34: 895. [3] Staack D, Farouk B, Gutsol A, et al. Plasma Sources Sci. Technol.，2005, 14: 700. [4] Vladimir I K. J. Phys. D., 2006, 39: R487. [5] Zhao Xiaofei, He Feng, OuYang Jiting. Phys. Lett. A, 2012, 376: 2057. [6] Robert R A, Vladimir I K. IEEE Trans. Plasma Sci., 2005, 33: 354. [7] Rajneesh K, Sanjay V K, Dhiraj B. Phys. Plasmas，2007, 14: 122101. [8] Feng Shuo, He Feng, OuYang Jiting. Chin. Phys. Lett.，2007, 24: 2304. [9] Herzberg G. Molecular Spectra and Molecular Structure, Ⅰ(分子光谱与分子结构，第1卷). Translated by WANG Ding-chang(王鼎昌，译). Beijing: Science Press(北京：科学出版社), 1983. [10] Nicholls R W. J. Quant. Spectrosc. Radiat. Transfer, 1962, 2: 433. [11] Sukhinin G I，Fedoseev A V. High Temperature，2006，44(2)：157. [12] Khudik V N, Shvydky A，Theodosiou C E. Phys. Plasmas，2006, 13: 034501.
