Suzaku Observation of the Anomalous X-ray Pulsar 1E 1841-045

TL;DR

This study used Suzaku observations to analyze the spectral properties of the anomalous X-ray pulsar 1E 1841-045, confirming consistent energy-dependent spectral models across a broad energy range and revealing insights into emission regions.

Contribution

The paper provides a comprehensive spectral analysis of 1E 1841-045 over a wide energy range, confirming model consistency and exploring phase-resolved emission characteristics.

Findings

Spectral models are consistent from 0.4 to 70 keV.

Two emission regions with thermal and non-thermal properties are identified.

Phase-resolved spectra show correlated blackbody temperatures and radii.

Abstract

We report the results of a Suzaku observation of the anomalous X-ray pulsar (AXP) 1E 1841-045 at a center of the supernova remnant Kes 73. We confirmed that the energy-dependent spectral models obtained by the previous separate observations were also satisfied over a wide energy range from 0.4 to ~70 keV, simultaneously. Here, the models below ~10 keV were a combination of blackbody (BB) and power-law (PL) functions or of two BBs wit h different temperatures at 0.6 - 7.0 keV (Morii et al. 2003), and that above ~20 keV was a PL function (Kuiper Hermsen Mendez 2004). The combination BB + PL + PL was found to best represent the phase-averaged spectrum. Phase-resolved spectroscopy indicated the existence of two emission regions, one with a thermal and the other with a non-thermal nature. The combination BB + BB + PL was also found to represent the phase-averaged spectrum well. However, we found that this model is physically unacceptable due to an excessively large area of the emission region of the blackbody. Nonetheless, we found that the temperatures and radii of the two blackbody components showed moderate correlations in the phase-resolved spectra. The fact that the same correlations have been observed between the phase-averaged spectra of various magnetars (Nakagawa et al. 2009) suggests that a self-similar function can approximate the intrinsic energy spectra of magnetars below ~10 keV.