The spectrum and dips of RE 0751+14: A joint evaluation of ROSAT and ASCA archival data

Kiziloglu, U
Baykal, Altan
Alev, M
Gogus, E
Using archival ASCA and ROSAT observations of RE 0751+14, X-ray energy spectra, pulse profiles and the results of pulse timing analysis are presented. The energy spectra are well-fitted by a blackbody model at low energy and a Raymond-Smith model at high energy, together with a partial covering absorber. A fluorescence emission line at 6.4 keV with an equivalent width similar to 220 eV was resolved for the first time.


Recent Spin Rate Measurements of 4U 1907+09
Sahiner, S.; İNAM, SITKI ÇAĞDAŞ; Baykal, Altan (2010-08-06)
In this study, X-ray spectral and pulse timing analysis of the high mass X-ray binary (HMXB) pulsar 4U 1907+09, based on the observations with RXTE are presented. Spin rate measurements indicate a new spin-down episode with a rate close to the previous steady spin-down rate. Orbital phase resolved spectroscopy reveals that the Hydrogen column density varies through the orbit reaching to its maximum value just after periastron. A slight spectral softening with increasing luminosity is aslo observed.
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The Spectral and temporal properties of MAXI J1409-619
Dönmez, Çağatay Kerem; Baykal, Altan; Department of Physics (2019)
In this thesis, spectral and timing analysis of the transient high-mass X-ray binary (HMXB) pulsar MAXI J1409-619 are presented. MAXI J1409-619 was discovered in October 2010, and went into an outburst in early December 2010 until February 2011. Observations of Swift and RXTE throughout this period are used in the thesis. The analysis results are in line with the assertion that MAXI J1409-619 is an accretion-powered pulsar. Time-resolved energy spectra of RXTE and Swift data confirm the previously reported ...
The torque and X-ray flux changes of OAO 1657-415
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Combining previously published pulse frequencies and BATSE measurements, we estimate the noise strengths (or power density estimates) of angular accelerations by using the root mean square residuals of angular velocity time series of OAO 1657-415 and present the power spectra. The statistical interpretation of the angular velocity fluctuations is consistent with a random walk model. In order to investigate the short term angular velocity fluctuations in detail, a structure function analysis is applied for a...
Low frequency flickering of TT Arietis: Hard and soft X-ray emission region
Baykal, Altan (1997-01-01)
Using archival ASCA observations of TT Arietis, X-ray energy spectra and power spectra of the intensity time series are presented for the first time. The energy spectra are well-fitted by a two continuum plasma emission model with temperatures similar to 1 keV and similar to 10 keV. A coherent feature at similar to 0.643 mHz appeared in the power spectra during the observation.
Citation Formats
U. Kiziloglu, A. Baykal, M. Alev, and E. Gogus, “The spectrum and dips of RE 0751+14: A joint evaluation of ROSAT and ASCA archival data,” ASTROPHYSICS AND SPACE SCIENCE, pp. 191–203, 1998, Accessed: 00, 2020. [Online]. Available: