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Instability of the 13.8 day period in X-ray emission from 4U1700-377

JaeSub Hong·Charles J. Hailey
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Abstract

We present a new result on long-term periodicity searches of the X-ray emission from 4U1700-377 using RXTE ASM and CGRO BATSE data. The hard X-ray data (20 - 200 keV) from early BATSE observations (1780 days from JD 2448370, before RXTE observations started) show evidence of a 13.8 day periodicity. The long term periodicity became substantially less prominent in the data from later BATSE observations and in the soft X-ray data from the ASM (2 - 10 keV) observations. We demonstrate that disk precession models can explain the 13.8 day period and its instability in the X-ray emission from 4U1700-377.

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JaeSub Hong, Charles J. Hailey. 2003-09-23. Instability of the 13.8 day period in X-ray emission from 4U1700-377. https://doi.org/10.1086/379700

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