真空紫外氙共振辐射源的研究

STUDIES ON THE VACUUM ULTRAVIOLET XENON RESONANCE RADIATION SOURCES

供研究的真空紫外(VUV)氙共振辐射源是一射频激发的、直径12mm长40mm的氦-氙放电等离子体.用四能级氙原子模型计算了氦-氙混合气不同比例和压强时的VUV输出特性,并用事先绝对标定的VUV探测系统测定了各种放电条件下的VUV输出.理论计算和实验测量符合较好.研究表明,在充气400Pa,含氙量2.5%时,此辐射源的VUV(λ=147.0nm)轴向亮度有最大值10W/(sr·m^2),即7.4×10^(17)个光子/(sr·m^2·s).

The studied vacuum ultraviolet (VUV)radiation source was a He-Xe discharge plasma of diameter 12mm with length of 40mm, which was excited by a r-f electrodeless discharge (120 MHz,l W). A xenon four atomic energy level computational model was proposed to facilitate the calculation. The data related to electron densities and temperatures,which were indispensable for solving the model, were obtained by double probe techniques. The model was then solved numerically by a computer and the VUV radiation output characteristics were obtained. The VUV output radiances of the He-Xe plasma at various conditions were also experimentally measured by an absolutely calibrated VUV spectral detect system. The experimental results were in reasonable agreement with the theoretical calculation. It was found that the maximum axial radiance about 10 W/(sr·m^2), i.e. 7.4×10^(17)photons/(sr·m^2·s), was reached in the He-Xe discharge plasma at 2.5% Xe and pressure 400 Pa.