中文摘要：

飞行时间质谱的离子峰形中包含了离子产生时的速度分布和空间分布信息。了解速度和空间分布对离子峰形的影响，可以根据峰形推测离子的产生机理。运用概率密度理论建立了一套飞行时间质谱的峰形模拟的方法和程序，并通过模拟分析考察了不同的空间分布和速度分布对离子峰形的影响。在偏离空间聚焦条件下，离子峰形显示了空间分布的信息。

英文摘要：

The peak shape of time of-flight mass spectrum contains information of ion initial spatial and velocity distributions. Information how ion initial spatial and velocity distributions influence the peak shape will help to analyze ion formation mechanism. A peak shape simulation program of TOF-MS based on probability was developed, and the effects of ionic initial spatial and velocity distributions on ionic peak shape were studied. The ionic spatial distributions can be acquired from ion peak shape under deviated space focus condition. The program provides a feasible approach for ion source analysis.