Comprehensive analysis of the transient X-ray pulsar MAXI J1409 619

Donmez, C. K.
Serim, Muhammed Miraç
Inam, S. C.
Sahiner, S.
Serim, D.
Baykal, Altan
We probe the properties of the transient X-ray pulsar MAXI J1409-619 through RXTE and Swift follow-up observations of the outburst in 2010. We are able to phase-connect the pulse arrival times for the 25 d episode during the outburst. We suggest that either an orbital model (with P-orb similar or equal to 14.7(4) d) or a noise process due to random torque fluctuations (with S-r approximate to 1.3 x 10(-18) Hz(2) S-2 Hz(-1)) is plausible to describe the residuals of the timing solution. The frequency derivatives indicate a positive torque-luminosity correlation, which implies temporary accretion disc formation during the outburst. We also discover several quasiperiodic oscillations in company with their harmonics whose centroid frequencies decrease as the source flux decays. The variation of the pulsed fraction and spectral power-law index of the source with X-ray flux is interpreted as the sign of transition from a critical to a subcritical accretion regime at the critical luminosity within the range of 6 x 10(37)-1.2 x 10(38) erg s(-1). Using pulse-phase-resolved spectroscopy, we show that the phases with higher flux tend to have lower photon indices, indicating that the polar regions produce spectrally harder emission.


RXTE and Swift Observations of SWIFT J0513.4-6547
Sahiner, S.; Serim, Muhammed Miraç; Baykal, Altan; İNAM, SITKI ÇAĞDAŞ (Oxford University Press (OUP), 2016-02-11)
We present timing and spectral analysis of Swift-XRT (X-ray Telescope) and RXTE-PCA (Rossi X-ray Timing Explorer-proportional Counter Array) observations of the transient Be/X-ray pulsar SWIFT J0513.4-6547 during its outburst in 2009 and its rebrightening in 2014. From 2009 observations, short-term spin-up rate of the source after the peak of the outburst is found to have about half of the value measured at the peak of the outburst by Coe et al. When the source is quiescent between 2009 and 2014, average sp...
Analysis of RXTE-PCA Observations of SMC X-1
İNAM, SITKI ÇAĞDAŞ; Baykal, Altan; Beklen, E. (Oxford University Press (OUP), 2010-03-21)
We present timing and spectral analysis of Rossi X-ray Timing Explorer-Proportional Counter Array observations of SMCX-1 between 1996 January and 2003 December. From observations around 1996 August 30 with a time-span of similar to 6 d, we obtain a precise timing solution for the source and resolve the eccentricity as 0.00089(6). We find an orbital decay rate of (P) over dot(orb)/P(orb) = -3.402(7) x 10(-6) yr(-1) which is close to the previous results. Using our timing analysis and the previous studies, we...
VERITAS discovery of > 200 GeV gamma-ray emission from the intermediate-frequency-peaked BL Lacertae object W Comae
Acciari, V. A.; et. al. (IOP Publishing, 2008-09-10)
We report the detection of very high energy gamma- ray emission from the intermediate- frequency- peaked BL Lacertae object W Comae (z = 0.102) by VERITAS. The source was observed between 2008 January and April. A strong outburst of gamma-ray emission was measured in the middle of March, lasting for only 4 days. The energy spectrum measured during the two highest flare nights is fit by a power law and is found to be very steep, with a differential photon spectral index of Gamma = 3.81 +/- 0.35(stat) +/- 0.3...
Discovery of a transient magnetar: XTE J1810-197
Ibrahim, AI; Markwardt, CB; Swank, JH; Ransom, S; Roberts, M; Kaspi, V; Woods, PM; Safi-Harb, S; Balman, Şölen; Parke, WC; Kouveliotou, C; Hurley, K; Cline, T (IOP Publishing, 2004-07-01)
We report the discovery of a new X-ray pulsar, XTE J1810 - 197, that was serendipitously discovered on 2003 July 15 by the Rossi X-Ray Timing Explorer (RXTE) while observing the soft gamma repeater SGR 1806 - 20. The pulsar has a 5.54 s spin period, a soft X-ray spectrum ( with a photon index of approximate to 4), and is detectable in earlier RXTE observations back to 2003 January but not before. These show that a transient outburst began between 2002 November 17 and 2003 January 23 and that the source's pe...
Frequency-resolved spectroscopy of XB1323-619 using XMM-Newton data: detection of a reflection region in the disc
Balman, Şölen (Oxford University Press (OUP), 2010-09-21)
We present the frequency-resolved energy spectra (FRS) of the low-mass X-ray binary dipper XB1323-619 during persistent emission in four different frequency bands using an archival XMM-Newton observation. FRS method helps to probe the inner zones of an accretion disc. XB1323-619 is an Atoll source and a type-I burster. We find that the FRS is well described by a single blackbody component with kT in a range 1.0-1.4 keV responsible for the source variability in the frequency ranges of 0.002-0.04 and 0.07-0.3...
Citation Formats
C. K. Donmez, M. M. Serim, S. C. Inam, S. Sahiner, D. Serim, and A. Baykal, “Comprehensive analysis of the transient X-ray pulsar MAXI J1409 619,” MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, pp. 1768–1783, 2020, Accessed: 00, 2020. [Online]. Available: