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Recurrent ~24 h Periods in RXTE ASM Data

S. A. Farrell·P. M. O'Neill·R. K. Sood
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Abstract

Analysis of data from the Rossi X-ray Timing Explorer satellite's All Sky Monitor instrument for several X-ray binary sources has identified a recurrent \~24 h period. This period is sometimes highly significant, giving rise to the possibility of it being identified as an orbital or super-orbital period. Further analysis has revealed the same period in a number of other X-ray sources. As a result this period has been discounted as spurious, described variously as arising from daily variations in background levels and beating between the sampling period and long-term secular trends in the light curves. We present here an analysis of the spurious periods and show that the dominant mechanism is in fact spectral leakage of low-frequency power present in the light curves.

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S. A. Farrell, P. M. O'Neill, R. K. Sood. 2005-07-12. Recurrent ~24 h Periods in RXTE ASM Data. https://doi.org/10.1071/as04081

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