Kilo-hertz QPO and X-ray Bursts in 4U 1608-52 in Low Intensity State

W. Yu; S. N. Zhang; B . A. Harmon; W. S. Paciesas; C. R. Robinson; J. E. Grindlay; P. Bloser; D. Barret; E. C. Ford; M. Tavani; P. Kaaret

doi:10.1063/1.54145

arXiv · astro-ph/9710069

Kilo-hertz QPO and X-ray Bursts in 4U 1608-52 in Low Intensity State

W. Yu·S. N. Zhang·B . A. Harmon·W. S. Paciesas·C. R. Robinson·J. E. Grindlay·P. Bloser·D. Barret·E. C. Ford·M. Tavani·P. Kaaret

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Abstract

We present the results from RXTE/PCA observations of 4U 1608-52 in its island state on March 15, 18 and 22 of 1996. Three type I X-ray bursts were detected in one RXTE orbit on March 22. We observed QPO features peaking at 567-800 Hz on March 15 and 22, with source fractional rms amplitude of 13%-17% and widths of 78-180 Hz in the power density spectra averaged over each spacecraft orbit. The rms amplitudes of these QPOs are positively correlated with the photon energy. The three X-ray bursts, with burst intervals of 16 and 8 minutes, have a duration of 16s. The blackbody emission region of the smallest X-ray burst among the three suggest it was a local nuclear burning. We also discuss a type I X-ray burst candidate in the observation.

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W. Yu, S. N. Zhang, B . A. Harmon, W. S. Paciesas, C. R. Robinson, J. E. Grindlay, P. Bloser, D. Barret, E. C. Ford, M. Tavani, P. Kaaret. 1997-10-09. Kilo-hertz QPO and X-ray Bursts in 4U 1608-52 in Low Intensity State. https://doi.org/10.1063/1.54145

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