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arXiv · 2203.08996

Time domain methods for X-ray and gamma-ray astronomy

Eric D. Feigelson·Vinay L. Kashyap·Aneta Siemiginowska
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Abstract

A variety of statistical methods for understanding variability in the time domain for low count rate X-ray and gamma-ray sources are explored. Variability can be detected using nonparametric (Anderson-Darling and overdispersion tests) and parametric (sequential likelihood-based tests) tools. Once detected, variability can be characterized by nonparametric (autocorrelation function, structure function,wavelet analysis) and parametric (multiple change point model such as Bayesian Blocks, integer autoregressive models, C-statistic and Poisson regression) methods. New multidimensional variability detection approaches are outlined. Software packages designed for high energy data analysis are deficient but tools are available in the R statistical software environment. Most of the methods presented here are not commonly used in high energy astronomy.

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Eric D. Feigelson, Vinay L. Kashyap, Aneta Siemiginowska. 2022-03-17. Time domain methods for X-ray and gamma-ray astronomy. https://doi.org/10.1007/978-981-16-4544-0_135-1

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