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Long-term variability in the X-ray emission of RX J0720.4-3125

Cor P. de Vries·Jacco Vink·Mariano Mendez·Frank Verbunt
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Abstract

We detect a gradual, long-term change in the shape of the X-ray spectrum of the isolated neutron star RX J0720.4-3125, such that the spectrum of the source can no longer be described as a blackbody spectrum. The change is accompanied by an energy-dependent change in the pulse profile. If the X-ray emission is influenced by the magnetic field of the pulsar, these changes in spectral shape may point to precession of the neutron star.

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Cor P. de Vries, Jacco Vink, Mariano Mendez, Frank Verbunt. 2004-01-12. Long-term variability in the X-ray emission of RX J0720.4-3125. https://doi.org/10.1051/0004-6361%3A20040009

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