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arXiv · 2412.18439

Statistical theory of cumulant mapping in an imperfect apparatus

S. Patchkovskii·J. Mikosch
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Abstract

Cumulant mapping has been recently suggested [Frasinski, Phys. Chem. Chem. Phys. 24, 207767 (2022)] as an efficient approach to observing multi-particle fragmentation pathways, while bypassing the restrictions of the usual coincidence-measurement approach. We present a formal analysis of the cumulant-mapping technique in the presence of moderate external noise, which induces spurious correlations between the fragments. Suppression of false-cumulant signal may impose severe restrictions on the stability of the experimental setup and/or the permissible average event rate, which increase with the cumulant order. We demonstrate that cumulant mapping in an imperfect apparatus remains competitive for dominant processes and for pathways with a background-free marker fragment. We further show that the false-cumulant contributions increase faster than linearly with the average event rate, providing a simple test for the experimental data analysis.

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S. Patchkovskii, J. Mikosch. 2024-12-24. Statistical theory of cumulant mapping in an imperfect apparatus. https://doi.org/10.1103/physreva.111.043108

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