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arXiv · astro-ph/0110400

Correlation between Break Frequency and Power Density Spectrum Slope for the X-ray Source Cygnus X-2: RXTE/PCA Data

Sergey Kuznetsov
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Abstract

We present results of RXTE observations of the X-ray source Cyg X-2 during 1996-1999. Its power density spectra in the 0.1-128-Hz band are fitted by a model that takes into account the power-law spectral behavior at frequencies below and above the break frequency, with an introduction of one or more Lorenz lines to describe the peaks of quasi-periodic oscillations that correspond to the horizontal branch of the Z track. The RXTE observations have revealed a positive correlation between the break frequency and the indices of the two parts of the spectrum. The spectrum steepens with increasing break frequency both above and below the break frequency.

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Sergey Kuznetsov. 2001-10-17. Correlation between Break Frequency and Power Density Spectrum Slope for the X-ray Source Cygnus X-2: RXTE/PCA Data. https://doi.org/10.1134/1.1424361

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