Internal cumulants for femtoscopy with fixed charged multiplicity

Date
2013
Journal Title
Journal ISSN
Volume Title
Publisher
Hindawi Publishing Corporation
Abstract
A detailed understanding of all effects and influences on higher-order correlations is essential. At low charged multiplicity, the effect of a non-Poissonian multiplicity distribution can significantly distort correlations. Evidently, the reference samples with respect to which correlations are measured should yield a null result in the absence of correlations. We show how the careful specification of desired properties necessarily leads to an average-of-multinomials reference sample. The resulting internal cumulants and their averaging over several multiplicities fulfill all requirements of correctly taking into account non-Poissonian multiplicity distributions as well as yielding a null result for uncorrelated fixed-N samples. Various correction factors are shown to be approximations at best. Careful rederivation of statistical variances and covariances within the frequentist approach yields errors for cumulants that differ from those used so far. We finally briefly discuss the implementation of the analysis through a multiple event buffer algorithm.
Description
CITATION: Eggers, H. C. & Buschbeck, B. 2013. Internal cumulants for femtoscopy with fixed charged multiplicity. Advances in High Energy Physics, 2013, Article ID 230515, doi:10.1155/2013/230515.
The original publication is available at https://www.hindawi.com/journals/ahep
Keywords
Femtoscopy, Cumulants, Multiplicity (Mathematics), Pairing correlations (Nuclear physics), Probabilities, Non-Poissonian multiplicity distribution
Citation
Eggers, H. C. & Buschbeck, B. 2013. Internal cumulants for femtoscopy with fixed charged multiplicity. Advances in High Energy Physics, 2013, Article ID 230515, doi:10.1155/2013/230515.