论文标题
累积映射作为多维光谱法的基础
Cumulant mapping as the basis of multi-dimensional spectrometry
论文作者
论文摘要
累积映射通过对其部分进行采样来采用整体的统计重建。在这项工作中开发的理论形式并扩展了“多折”或“多维”协方差映射的临时方法。已经为第6累积剂的预期值得出了明确的公式，并且已经计算出第4累积剂的方差。已经描述了一种将这些公式扩展到较高累积物的方法。公式考虑了降低的片段检测效率和不相关事件的背景。可以使用补充材料中包含的MATLAB代码估算将统计噪声抑制至所需水平所需的样品数量。该理论可用于评估研究飞秒或X射线自由电子激光器引起的分子碎片的实验可行性。它也与将生物分子的常规质谱分析扩展到多个维度有关。
Cumulant mapping employs a statistical reconstruction of the whole by sampling its parts. The theory developed in this work formalises and extends ad hoc methods of `multi-fold' or `multi-dimensional' covariance mapping. Explicit formulae have been derived for the expected values of up to the 6th cumulant and the variance has been calculated for up to the 4th cumulant. A method of extending these formulae to higher cumulants has been described. The formulae take into account reduced fragment detection efficiency and a background from uncorrelated events. Number of samples needed for suppressing the statistical noise to a required level can be estimated using Matlab code included in Supplemental Material. The theory can be used to assess the experimental feasibility of studying molecular fragmentations induced by femtosecond or x-ray free-electron lasers. It is also relevant for extending the conventional mass spectrometry of biomolecules to multiple dimensions.
