We present the results of a spectral analysis of the central region of the mixed-morphology supernova remnant HB 9 .
A prior Ginga observation of this source detected a hard X-ray component above 4 keV and the origin of this particular X-ray component is still unknown .
Our results demonstrate that the extracted X-ray spectra are best represented by a model consisting of a collisional ionization equilibrium plasma with a temperature of \sim 0.1–0.2 keV ( interstellar matter component ) and an ionizing plasma with a temperature of \sim 0.6–0.7 keV and an ionization timescale of > 1 \times 10 ^ { 11 } cm ^ { -3 } s ( ejecta component ) .
No significant X-ray emission was found in the central region above 4 keV .
The recombining plasma model reported by a previous work does not explain our spectra .