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arXiv · 0806.2530

SWIFT J1753.5-0127: a surprising optical/X-ray cross-correlation function

Martin Durant·Poshak Gandhi·Tariq Shahbaz·Andy Fabian·Jon Miller·V. S. Dhillon·Tom R. Marsh
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Abstract

We have conducted optical and X-ray simultaneous observations of SWIFT J1753.5-0127 with RXTE and ULTRACAM, while the system persisted in its relatively bright low/hard state. In the cross-correlation function (CCF), we find that the optical leads the X-rays by a few seconds with a broad negative peak, and has a smaller positive peak at positive lags. This is markedly different from what was seen for the similarly interesting system XTE J1118+480, and the first time such a correlation function has been so clearly measured. Furthermore, there appears to be a significant variation of the correlation with X-ray energy. We suggest a physical scenario for its origin.

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Martin Durant, Poshak Gandhi, Tariq Shahbaz, Andy Fabian, Jon Miller, V. S. Dhillon, Tom R. Marsh. 2008-06-16. SWIFT J1753.5-0127: a surprising optical/X-ray cross-correlation function. https://doi.org/10.1086/590906

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