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The atoll source 4U 1608-52 is not a Z source

S. van Straaten·M. van der Klis·M. Mendez
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Abstract

We have studied the spectral and timing behaviour of the atoll source 4U 1608-52. We find that the timing behaviour of 4U 1608-52 is almost identical to that of the atoll sources 4U 0614+09 and 4U 1728-34. Recently Muno, Remillard & Chakrabarty (2002) and Gierlinski & Done (2002) suggested that the atoll sources trace out similar three-branch patterns as the Z sources. The timing behaviour is not consistent with the idea that 4U 1608-52 traces out a three-branched Z shape in the color-color diagram along which the timing properties vary gradually.

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S. van Straaten, M. van der Klis, M. Mendez. 2002-07-30. The atoll source 4U 1608-52 is not a Z source. https://arxiv.org/abs/astro-ph/0207646

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