A Unique Neutron Star: Detailed Spectral and Theoretical Analysis of 1E1207.4-5209

Kaya Mori

Canadian Institute for Theoretical Astrophysics


1E1207.4-5209 is unique because it is the only isolated neutron star with multiple spectral features. We present our detailed analysis of the 260 ksec XMM-Newton data focusing on the putative absorption features at 2.1 and 2.8 keV reported by Bignami et al. 2003. Our statistical tests show the 3rd and 4th feature are insignificant, and only the two broad absorption features previously reported are significant. We have also confirmed that the residuals are consistent in strength and position with the instrument Au-M residuals observed in 3C273. We also present the results from our recent phase-resolved spectral analysis of 1E1207. At the end, we discuss our model for the two absorption features in terms of atomic transition lines from highly-ionized Oxygen or Neon and compare that picture with other competing models. Future high resolution spectroscopy is essential to elucidate the surface composition of 1E1207 and to understand why 1E1207 is unique compared to other isolated neutron stars.

Go back to the program page