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

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.


Timing studies of X Persei and the discovery of its transient quasi-periodic oscillation feature
Acuner, Z.; İNAM, SITKI ÇAĞDAŞ; Sahiner, S.; Serim, Muhammed Miraç; Baykal, Altan; Swank, J. (2014-10-11)
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We analysed the Rossi X-ray Timing Explorer (RXTE) archival data of 1E 1048.1-5937 covering a time-span of more than one year. The spin-down rate of this source decreases by similar to 30 per cent during the observation. We could not resolve the X-ray flux variations because of contamination by eta Carinae. We find that the level of pulse frequency fluctuations of 1E 1048.1-5937 is consistent with typical noise levels of accretion-powered pulsars. Recent RXTE observations of 1E 2259+586 have shown a constan...
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Spin-down rate of 1E 2259+586 from RXTE observation
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We present new X-ray observations of the X-ray pulsar 1E 2259+586, obtained during March 1997, with the Rossi X-Ray Timing Explorer (RXTE). We have measured the pulse frequency derivative (nu) over dot = (-1.08 +/- 0.04) x 10(-14) Hz s(-1) from pulse arrival times obtained in a sequence of 5 observations spread over one month. This (nu) over dot is consistent with the long term spin-down trend. We also found that the observed X-ray luminosity is consistent with that measured at quiescent X-ray flux levels b...
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.