激光诱导Al表面等离子体温度的发射谱诊断

探测了脉冲能量0.3 J波长1064 nm的纳秒激光聚焦Al表面诱导的等离子体200-900 nm范围的发射谱.分析了线状谱的基本规律，根据谱线的强度，考虑到光谱仪与电荷耦合器件(charge coupled device, CCD)的探测效率，通过线性拟合给出了等离子体中Al Ⅰ、Al Ⅱ、N Ⅰ、O Ⅰ粒子的激发温度.根据谱线的半高宽计算了等离子体电子密度，进而计算了等离子中Al Ⅰ的电离温度.结果表明，在等离子体状态快速演化过程中，不同粒子的电离、激发与退激存在较大差异，Al Ⅱ、Al Ⅰ相对于N Ⅰ、O Ⅰ有较高的激发温度，并且等离子体中Al Ⅰ的电离温度高于所有粒子的激发温度.

The diagnosis of temperature of laser-induced Al surface plasma based on the linear emission spectrum

The emission spectra in the range of 200-900 nm of the nanosecond laser-focused Al surface-induced plasma with a pulse energy of 0.3J and wavelength of 1064nm are detected. The basic law of the linear spectrum is analyzed, and based on the strength of the spectral line and the detection efficiency of the spectrometer and CCD, the excitation temperatures of the Al I, Al II, N I and O I particles in the plasma are given by linear fitting,. The plasma electron density is calculated from the half-width of the line, and subsequently the ionization temperature of Al I in the plasma is calculated. The results show that the ionization, excitation and dissociation differ greatly from particle to particle during the rapid evolution of the plasma state, the Al II and Al I have the high excitation temperature relative to the N I, O I, and the ionization temperature of the Al I in the plasma is higher than the excitation temperatures of all the particles.