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On the time variability of gamma-ray sources: A numerical analysis of variability indices

Diego F. Torres·M. E. Pessah·Gustavo E. Romero
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Abstract

We present a Monte Carlo analysis of the recently introduced variability indices $τ$ (Tompkins 1999) and $I$ (Zhang et al. 2000 & Torres et al. 2001) for $γ$-ray sources. We explore different variability criteria and prove that these two indices, despite the very different approaches used to compute them, are statistically correlated (5 to 7$σ$). This conclusion is maintained also for the subset of AGNs and high latitude ($|b|>10$ deg) sources, whereas the correlation is lowered for the low latitude ones, where the influence of the diffuse galactic emission background is strong.

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Diego F. Torres, M. E. Pessah, Gustavo E. Romero. 2001-10-26. On the time variability of gamma-ray sources: A numerical analysis of variability indices. https://doi.org/10.1002/1521-3994(200110)322%3A4%3C223%3A%3Aaid-asna223%3E3.0.co%3B2-k

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