RX J0720.4-3125 belongs to a group of radio-quiet isolated neutron stars, whosespectra are characterized by a black-body spectrum plus one or more broadabsorption features. It is unique in that its black-body temperature, and thedepth of the absorption feature is variable. The cause for this spectralevolution is unclear, but one proposed model is free precession of a neutronstar with two hot spots. Observing in the next XMM-Newton cycle will completethe coverage of a putative precession cycle with a period of 7.1+/-0.5 yr. Thisputs the precession hypothesis to the ultimate test.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2009-03-21T12:50:08Z/2009-03-21T20:19:43Z
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 Jacco Vink, 2010, 'RX J0720 evolution: precession comma glitching comma the last flutterings of a magnetarquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-rcztiat
