Interferometry imaging for the evolving source in heavy ion collisions at HIRFL-CSR energy

Imaging analysis of two-pion interferometry is performed for an evolving particle-emitting source in heavy ion collisions at HIRFL-CSR energy. The source evolution is described by the relativistic hydrodynamics in (2+1) dimensions. The model-independent characteristic quantities of the source are investigated and compared with the interferometry results obtained by the usual Gaussian formula fit. It is found that the first- order source function moments can describe the source sizes. The ratio of the normalized standard deviation σ to the first-order moment R, σ/R, is sensitive to the shape of the source function.     

镱铒共掺硅酸盐玻璃三波段光致发光特性数值分析

考虑两级合作上转换、激发态吸收、交叉弛豫等非线性效应,建立了镱铒共掺硅酸盐玻璃材料9个能级的11个速率方程。唯象地构造了合作上转换系数随镱铒掺杂浓度的变化函数,数值模拟了镱铒共掺硅酸盐玻璃1530,664,549nm 3个波段的光致发光强度与掺杂浓度、抽运功率的变化关系。计算结果表明：掺铒浓度一定,镱浓度增加时,对于1530nm荧光而言,有最佳的掺镱浓度,但红光和绿光荧光强度随掺镱浓度始终增强;保持镱铒掺杂浓度不变,抽运功率增加时,3种荧光强度均单调增强,差别在于增幅速率不同,且近红外光强有饱和趋势。计算结果与实验测量相吻合。