Timing studies on RXTE observations of SAX J2103.5+4545

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2007-01-21
Baykal, Altan
Stark, M. J.
Heffner, C. M.
Erkoca, A. E.
Swank, J. H.
SAX J2103.5+4545 has been continuously monitored for similar to 900 d by the Rossi X-ray Timing Explorer (RXTE) since its outburst in 2002 July. Using these observations and previous archival RXTE observations of SAX J2103.5+4545, we refined the binary orbital parameters and find the new orbital period as P = (12.665 36 +/- 0.000 88) d and the eccentricity as 0.4055 +/- 0.0032. With these new orbital parameters, we constructed the pulse frequency and pulse frequency derivative histories of the pulsar and confirmed the correlation between X-ray flux and pulse frequency derivative presented by Baykal, Stark & Swank. We constructed the power spectra for the fluctuations of pulse frequency derivatives and found that the power-law index of the noise spectra is 2.13 +/- 0.6. The power-law index is consistent with random walk in pulse frequency derivative and is the steepest among the HMXRBs. X-ray spectra analysis confirmed the inverse correlation trend between power-law index and X-ray flux found by Baykal et al.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

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Citation Formats
A. Baykal, M. J. Stark, C. M. Heffner, A. E. Erkoca, and J. H. Swank, “Timing studies on RXTE observations of SAX J2103.5+4545,” MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, pp. 1108–1114, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41726.