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RXTE Observations of 1A 1744-361: Correlated Spectral and Timing Behavior

Sudip Bhattacharyya·Tod E. Strohmayer·Jean H. Swank·Craig B. Markwardt
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Abstract

We analyze Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) data of the transient low mass X-ray binary (LMXB) system 1A 1744-361. We explore the X-ray intensity and spectral evolution of the source, perform timing analysis, and find that 1A 1744-361 shows `atoll' behavior during the outbursts. The color-color diagram indicates that this LMXB was observed in a low intensity spectrally hard (low-hard) state and in a high intensity `banana' state. The low-hard state shows a horizontal pattern in the color-color diagram, and the previously reported `dipper QPO' appears only during this state. We also perform energy spectral analyses, and report the first detection of broad iron emission line and iron absorption edge from 1A 1744-361.

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Sudip Bhattacharyya, Tod E. Strohmayer, Jean H. Swank, Craig B. Markwardt. 2006-07-20. RXTE Observations of 1A 1744-361: Correlated Spectral and Timing Behavior. https://doi.org/10.1086/507786

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