De Luca, A;
Salvetti, D;
Sartori, A;
Esposito, P;
Tiengo, A;
Zane, S;
Turolla, R;
... Bignami, GF; + view all
(2012)
A time-variable, phase-dependent emission line in the X-ray spectrum of the isolated neutron star RXJ0822–4300.
Monthly Notices of the Royal Astronomical Society: Letters
, 421
(1)
L72-L76.
10.1111/j.1745-3933.2011.01209.x.
![[thumbnail of 1333411.pdf]](https://discovery-pp.ucl.ac.uk/style/images/fileicons/text.png) Preview |
Text
1333411.pdf Download (222kB) |
Abstract
RX J0822−4300 is the central compact object associated with the Puppis A supernova remnant. Previous X-ray observations suggested RX J0822−4300 to be a young neutron star with a weak dipole field and a peculiar surface temperature distribution dominated by two antipodal spots with different temperatures and sizes. An emission line at 0.8 keV was also detected. We performed a very deep (130-ks) observation with XMM–Newton, which allowed us to study in detail the phase-resolved properties of RX J0822−4300. Our new data confirm the existence of a narrow spectral feature, best modelled as an emission line, only seen in the ‘soft’-phase interval – when the cooler region is best aligned to the line of sight. Surprisingly, comparison of our recent observations to the older ones yields evidence for a variation in the emission-line component, which can be modelled as a decrease in the central energy from ∼0.80 keV in 2001 to ∼0.73 keV in 2009–10. The line could be generated via cyclotron scattering of thermal photons in an optically-thin layer of gas, or, alternatively, it could originate in low-rate accretion by a debris disc. In any case, a variation in energy, pointing to a variation of the magnetic field in the line-emitting region, cannot be easily accounted for.
| Type: | Article |
|---|---|
| Title: | A time-variable, phase-dependent emission line in the X-ray spectrum of the isolated neutron star RXJ0822–4300 |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1111/j.1745-3933.2011.01209.x |
| Publisher version: | https://doi.org/10.1111/j.1745-3933.2011.01209.x |
| Language: | English |
| Additional information: | This is the published version of record. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | stars: neutron; pulsars: general; X-rays: individual: RX J0822−4300 |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Space and Climate Physics |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/1333411 |
Archive Staff Only
 |
View Item |
