Related papers: Evidence of a decrease of kHz QPO peak separation …

Using all available archival data from the Rossi X-ray Timing Explorer (RXTE), we follow the frequency of the kilo-Hz QPOs in three low luminosity neutron star low mass X-ray binaries; namely 4U 1636-536, 4U 1608-522, and 4U1735-44.…

We report the detection of quasi-periodic oscillation (QPO) at ~41 mHz in the transient high-mass Be/X-ray binary pulsar 4U~0115+634 using data from the Rossi X-Ray Timing Explorer (RXTE) observatory. The observations used in the present…

We analysed all archival RXTE observations of the neutron-star low-mass X-ray binary 4U 1636-53 up to May 2010. In 528 out of 1280 observations we detected kilohertz quasi-periodic oscillations (kHz QPOs), with ~ 65% of these detections…

In observations with the Rossi X-ray Timing Explorer we have discovered quasi-periodic oscillations (QPOs) near 1 kHz from 4U 1705-44, a low--mass X-ray binary with a neutron star classified as an atoll source. In six separate observations,…

We have discovered a 7.06+-0.08 Hz quasi-periodic oscillation (QPO) in the X-ray flux of the low-luminosity low-mass X-ray binary (LMXB) and atoll source 4U 1820-30. This QPO was only observable at the highest observed mass accretion rate,…

We present new results based on observations carried out with the Rossi X-ray Timing Explorer during the decay of an outburst of the low-mass X-ray binary (LMXB) and atoll source 4U 1608-52. Our results appear to resolve, at least in 4U…

We observed the low-mass X-ray binary and Z source GX 17+2 with the Rossi X-ray Timing Explorer during 6-8 Feb 1997, 1-4 Apr 1997, and 26-27 Jul 1997. The X-ray color-color diagram shows a clear Z track. Two simultaneous kHz quasi-periodic…

We report the discovery of kHz quasi periodic oscillations (QPOs) in three Rossi X-ray Timing Explorer observations of the low mass X-ray binary (LMXB) XTE J1701-407. In one of the observations we detect a kHz QPO with a characteristic…

We present results of RXTE observations of the low-mass X-ray binary and atoll source 4U 1608$-$52 made over 9 days during the decline of an X-ray intensity outburst in March 1996. A fast-timing analysis shows a strong and narrow quasi…

We study the timing properties of the low mass X-ray binary 4U 1728-34 using recently released data from the Rossi X-Ray Timing Explorer. This binary, like many others with accreting neutron stars, is known to exhibit strong quasi-periodic…

We have carried out a systematic study of the properties of the kilo-Hertz quasi-periodic oscillations (QPO) observed in the X-ray emission of the neutron star low-mass X-ray binary 4U1608-52, using archival data obtained with the Rossi…

We present an analysis of the energy and frequency dependence of the Fourier time lags of the hectoHertz quasi-periodic oscillations (QPOs) and of the QPOs at the frequency at which the power density spectrum shows a break in the…

We have discovered two simultaneous kHz quasi-periodic oscillations (QPOs) in the Z source GX 340+0 with the Rossi X-ray Timing Explorer. The X-ray hardness-intensity and color-color diagram each show a full Z-track, with an extra limb…

Using the Rossi X-ray Timing Explorer we have measured 27 microsecond time delays in 830 Hz quasi-periodic oscillations (QPO) between 4-6 keV and 11-17 keV in 4U 1608-52, with high-energy photons lagging low energy photons, and found upper…

We report the discovery of a quasi-periodic oscillation (QPO) at 61.0+/-1.7 Hz with the Rossi X-Ray Timing Explorer in the low-mass X-ray binary and persistently bright atoll source GX 13+1 (4U 1811-17). The QPO had an rms amplitude of…

We present for the neutron-star low-mass X-ray binary 4U 1636$-$53, and for the first time for any source of kilohertz quasi-periodic oscillations (kHz QPOs), the two-dimensional behaviour of the fractional rms amplitude of the kHz QPOs in…

We re-analyzed two Rossi X-Ray Timing Explorer archival observations of the atoll source 4U 1820-30 in order to investigate the detailed time-frequency properties of the source during the intervals when a ~7 Hz QPO was detected by Wijnands…

The X-ray burster and dipper 4U1915-05 (also known as XB1916-053) was observed 19 times for a total exposure of roughly 140 ks between 1996 February and October with the proportional counter array (PCA) aboard Rossi X-ray Timing Explorer…

We report on the evolution of the timing of 4U1630-47 during its 1998 outburst using data obtained with the Rossi X-ray Timing Explorer (RXTE). The count rate and position in hardness-intensity, color-color diagrams and simple spectral fits…

We have detected large-amplitude 0.3-1.2 mHz quasi-periodic oscillations (QPOs) from the low-mass X-ray binary pulsar 4U 1626-67/KZ TrA, using UV photometry from HST and ground-based optical photometry. These 1 mHz QPOs, which have…