pith. sign in

arxiv: 1203.3708 · v1 · pith:7U6EWED4new · submitted 2012-03-16 · 🌌 astro-ph.HE

The continued spectral and temporal evolution of RX J0720.4-3125

classification 🌌 astro-ph.HE
keywords behaviourglitchj0720sevenspectralyearsarounddays
0
0 comments X
read the original abstract

RX J0720.4-3125 is the most peculiar object among a group of seven isolated X-ray pulsars (the so-called "Magnificent Seven"), since it shows long-term variations of its spectral and temporal properties on time scales of years. This behaviour was explained by different authors either by free precession (with a seven or fourteen years period) or possibly a glitch that occurred around $\mathrm{MJD=52866\pm73 days}$. We analysed our most recent XMM-Newton and Chandra observations in order to further monitor the behaviour of this neutron star. With the new data sets, the timing behaviour of RX J0720.4-3125 suggests a single (sudden) event (e.g. a glitch) rather than a cyclic pattern as expected by free precession. The spectral parameters changed significantly around the proposed glitch time, but more gradual variations occurred already before the (putative) event. Since $\mathrm{MJD\approx53000 days}$ the spectra indicate a very slow cooling by $\sim$2 eV over 7 years.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.