The Continued Spectral Evolution of the Neutron Star Rx J0720.4-3125
نویسنده
چکیده
We observed the isolated neutron star RX J0720.4-3125 with Chandra’s Low Energy Transmission Grating Spectrometer, following the XMM-Newton discovery of long term spectral evolution of this source. The new observation shows that the spectrum of RX J0720.4-3125 has continued to change in the course of 5 months. It has remained hard, similar to the last XMM-Newton observation, but the strong depression observed with XMMNewton at long wavelengths has disappeared. Contrary to the XMM-Newton observations, the new Chandra observation shows that the flux increase at short wavelengths and the decrease at long wavelengths do not necessarily occur simultaneously. Subject headings: stars: individual (RX J0720.4-3125) – stars: neutron – X-rays: stars
منابع مشابه
XMM-Newton RGS spectrum of RX J0720.4−3125: An absorption feature at 0.57 keV
Aims. By measuring the gravitational redshift of spectral features in the spectrum of thermal radiation emitted from neutron stars, useful constraints for the equation of state of superdense matter can be obtained via an estimate of the mass-to-radius ratio. We searched for spectral line features in the high-resolution X-ray spectrum of the isolated neutron star RX J0720.4−3125. Methods. Our ta...
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