Broad Fe lines have been detected in 10 neutron-star LMXBs. In two sources theFe line and kHz QPOs give consistent values for the inner radius of theaccretion disc, but measurements were not simultaneous. Using XMM-Newton/RXTEand Chandra/RXTE simultaneously, we have recently shown that in the LMXB 4U1636-53 the Fe line and the kHz QPO yield different disc radii. The frequenciesof the kHz QPOs correlate with the disc radius inferred from broad-band spectra,while the Fe line appears to change independently. We propose 5 simultaneousXMM-Newton/RXTE observations of the LMXB 4U 1728-34 with both a broad Fe lineand kHz QPOs, using the long-term variability of this source to test thedynamics and correlation of the radii inferred from the line and the kHz QPOs.
Instrument
EPN, OM, RGS1, RGS2
Temporal Coverage
2011-08-28T14:08:20Z/2011-10-07T13:16:25Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Prof Mariano Mendez, 2012, 'Probing the gravitational field around neutron stars with Fe lines and kHz QPOs', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-0kivalg
