Systematic evaluation of variability detection methods for eROSITA

Buchner J, Boller T, Bogensberger D, Malyali A, Nandra K, Wilms J, Dwelly T, Liu T (2022)


Publication Type: Journal article

Publication year: 2022

Journal

Book Volume: 661

DOI: 10.1051/0004-6361/202141099

Abstract

The reliability of detecting source variability in sparsely and irregularly sampled X-ray light curves is investigated. This is motivated by the unprecedented survey capabilities of eROSITA on board the Spektrum-Roentgen-Gamma observatory, providing light curves for many thousand sources in its final-depth equatorial deep-field survey. Four methods for detecting variability are evaluated: excess variance, amplitude maximum deviations, Bayesian blocks, and a new Bayesian formulation of the excess variance. We judge the false-detection rate of variability based on simulated Poisson light curves of constant sources, and calibrate significance thresholds. Simulations in which flares are injected favour the amplitude maximum deviation as most sensitive at low false detections. Simulations with white and red stochastic source variability favour Bayesian methods. The results are applicable also for the million sources expected in the eROSITA all-sky survey.

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How to cite

APA:

Buchner, J., Boller, T., Bogensberger, D., Malyali, A., Nandra, K., Wilms, J.,... Liu, T. (2022). Systematic evaluation of variability detection methods for eROSITA. Astronomy & Astrophysics, 661. https://doi.org/10.1051/0004-6361/202141099

MLA:

Buchner, Johannes, et al. "Systematic evaluation of variability detection methods for eROSITA." Astronomy & Astrophysics 661 (2022).

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