The nature of RX J1856.5-3754, the famous nearby radio-silent compact object,remains unknown because its rotational period has not been detected. However,the numerous X-ray observations of this puzzling source have been sensitive toperiods only above 20 ms. We argue that the observed X-ray and optical radiationof this source can be interpreted as thermal emission from peripheries of hotpolar caps of a millisecond pulsar, whose nonthermal emission in radio andX-rays is not observable because of an unfavorable orientation of the radiationbeams. To verify this hypothesis, we propose to observe this target with theEPIC-pn instrument operating in timing mode. The proposed observation will besensitive to millisecond pulsations with a pulsed fraction as low as 3%.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2004-04-17T21:55:45Z/2004-04-18T16:23:15Z
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, Dr VYACHESLAV ZAVLIN, 2005, 'THE ENIGMATIC SOURCE RX J1856.5-3754: IS IT A MILLISECOND PULSARquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-fqe230w
