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Low and high frequency Quasi-Periodic Oscillations in 4U1915-05

L. Boirin·D. Barret·J. F. Olive·J. E. Grindlay·P. F. Bloser
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Abstract

The burster and dipper Low Mass X-ray Binary (LMXB) 4U1915-05 (also known as XB1916-053) was observed by the Rossi X-ray Timing Explorer (RXTE) 19 times for a total exposure of 140 ks between 1996 February and October. Here we report on the discovery of Low Frequency (10-40 Hz) Quasi-Periodic Oscillations (LFQPOs) from 4U1915-05. The properties of the LFQPOs are related to the presence of the High Frequency QPOs (HFQPOs) detected simultaneously. We have observed a correlation between the LFQPO frequency and source count rate, as well as a correlation (linear) between the LFQPOs and HFQPOs. Both results cannot be explained by a Beat Frequency Model (BFM). They are also hardly compatible with predictions from the inner disk precession model.

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L. Boirin, D. Barret, J. F. Olive, J. E. Grindlay, P. F. Bloser. 1999-02-17. Low and high frequency Quasi-Periodic Oscillations in 4U1915-05. https://doi.org/10.1063/1.1434675

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