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arXiv · 2101.04201

A Minimal Timescale for the Continuum in 4U 1608-52 and Aql X-1

K. Mohamed·E. Sonbas·K. S. Dhuga·E. Göğüş·A. Tuncer·N. N. Abd Allah·A. Ibrahim
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Abstract

Similar to black-hole X-ray binary (BHXRB) transients, hysteresis-like state transitions are also seen in some neutron-star X-ray binaries (NSXRBs). Using a method based on wavelets and lightcurves constructed from archival RXTE observations, we extract a minimal timescale over the complete range of transitions for 4U 1608-52 during the 2002 and 2007 outbursts and the 1999 and 2000 outbursts for Aql X-1. We present evidence for a strong positive correlation between this minimal timescale and a similar timescale extracted from the corresponding power spectra of these sources.

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K. Mohamed, E. Sonbas, K. S. Dhuga, E. Göğüş, A. Tuncer, N. N. Abd Allah, A. Ibrahim. 2021-01-11. A Minimal Timescale for the Continuum in 4U 1608-52 and Aql X-1. https://doi.org/10.1093/mnrasl%2Fslab004

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