We present the analysis of the X-ray Multi-Mirror Mission ( XMM-Newton ) European Photon Imaging Camera ( EPIC ) data of the Galactic supernova remnant ( SNR ) CTB 109 ( G109.1–1.0 ) .
CTB 109 is associated with the anomalous X-ray pulsar ( AXP ) 1E 2259+586 and has an unusual semi-circular morphology in both the X-ray and the radio , and an extended X-ray bright interior region known as the ‘ Lobe ’ .
The deep EPIC mosaic image of the remnant shows no emission towards the west where a giant molecular cloud complex is located .
No morphological connection between the Lobe and the AXP is found .
We find remarkably little spectral variation across the remnant given the large intensity variations .
All spectra of the shell and the Lobe are well fitted by a single-temperature non-equilibrium ionization model for a collisional plasma with solar abundances ( kT \approx 0.5 - 0.7 keV , \tau = \int n _ { e } dt \approx 1 - 4 \times 10 ^ { 11 } s cm ^ { -3 } , \mbox { $N _ { H } $ } \approx 5 - 7 \times 10 ^ { 21 } cm ^ { -2 } ) .
There is no indication of nonthermal emission in the Lobe or the shell .
We conclude that the Lobe originated from an interaction of the SNR shock wave with an interstellar cloud .
Applying the Sedov solution for the undisturbed eastern part of the SNR , and assuming full equilibration between the electrons and ions behind the shock front , the SNR shock velocity is derived as v _ { s } = 720 \pm 60 km s ^ { -1 } , the remnant age as t = ( 8.8 \pm 0.9 ) \times 10 ^ { 3 } ~ { } d _ { 3 } yr , the initial energy as E _ { 0 } = ( 7.4 \pm 2.9 ) \times 10 ^ { 50 } ~ { } d _ { 3 } ^ { 2.5 } ergs , and the pre-shock density of the nuclei in the ambient medium as n _ { 0 } = ( 0.16 \pm 0.02 ) ~ { } d _ { 3 } ^ { -0.5 } cm ^ { -3 } , at an assumed distance of D = 3.0 ~ { } d _ { 3 } kpc .
Assuming CTB 109 and 1E 2259+586 are associated , these values constrain the age and the environment of the progenitor of the SNR and the pulsar .