ar X iv : a st ro - p h / 98 05 36 6 v 1 2 9 M ay 1 99 8 Quasi - periodic oscillations discovered in the new X - ray pulsar

ar X iv : a st ro - p h / 99 05 37 6 v 1 2 8 M ay 1 99 9 A 6 . 4 - hr positive superhump period in TV

ar X iv : a st ro - p h / 99 05 23 6 v 1 1 8 M ay 1 99 9 Strong Field Gravity and X - Ray Observations of 4 U 1820 – 30

The behavior of quasi-periodic oscillations (QPOs) at frequencies near 1 kHz in the x-ray emission from the neutron star x-ray binary 4U 1820-30 has been interpreted as evidence for the existence of the marginally stable orbit, a key prediction of strong-field general relativity. The signature of the marginally stable orbit is a saturation in QPO frequency, assumed to track inner disk radius, v...

ar X iv : a st ro - p h / 98 12 35 8 v 1 1 8 D ec 1 99 8 RXTE OBSERVATIONS OF LMC X - 1

The luminous X-ray binary and black-hole candidate LMC X-1 has been observed with the Rossi X-ray Timing Explorer (RXT E) to search for quasi-periodic oscillations (QPO), previously reported in its high state. The source was observed monthly in a series of nine observations. Analysis of the temporal variations shows no evidence for QPO or other periodic changes, but correlations between the hig...

ar X iv : a st ro - p h / 98 05 07 7 v 1 6 M ay 1 99 8 Long - Term X - ray Variability in GX 354 – 0

We report for the first time the detection of long-term X-ray variability in the bright bulge source GX 354–0 (=4U 1728–34) observed with the All Sky Monitor (ASM) on board the Rossi X-Ray Timing Explorer (RXTE). The 2-year RXTE ASM database reveals significant power at ∼ 72 days. Similar behaviour was seen in the 6-year Ariel 5 ASM database, but at a period of ∼ 63 days. The timescales and lig...

ar X iv : a st ro - p h / 98 09 36 7 v 1 2 8 Se p 19 98 RXTE OBSERVATIONS OF PSR J 1105 − 6107

We report on X-ray observations of the young, energetic radio pulsar PSR J1105−6107 obtained using the Rossi X-ray Timing Explorer. Our timing analysis of Proportional Counter Array data finds no evidence for X-ray pulsations from this source. We set a new upper limit on the pulsed X-ray flux from the pulsar of 18% in the 2-10 keV band, for a duty cycle of 0.5. Our improved upper limit supports...