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arXiv · 1204.1849

The rms-flux relations in different branches in Cyg X-2

Z. B. Li·L. M. Song·J. L. Qu·Y. J. Lei·J. Y. Nie·C. M. Zhang
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Abstract

In this paper, the rms-flux (root mean square-flux) relation along the Z-track of the bright Z-Source Cyg X-2 is analyzed using the observational data of Rossi X-ray Timing Explorer (RXTE). Three types of rms-flux relations, i.e. positive, negative, and 'arch'-like correlations are found in different branches. The rms is positively correlated with flux in normal branch (NB), but anti-correlated in the vertical horizontal branch (VHB). The rms-flux relation shows an 'arch'-like shape in the horizontal branch (HB). We also try to explain this phenomenon using existing models.

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Z. B. Li, L. M. Song, J. L. Qu, Y. J. Lei, J. Y. Nie, C. M. Zhang. 2012-04-09. The rms-flux relations in different branches in Cyg X-2. https://doi.org/10.1007/s10509-012-1086-6

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