We report on XMM-Newton observations of G32.45$+$0.1 and G38.55$+$0.0. These were discovered as diffuse hard X-ray sources by the ASCA Galactic Plane Survey, but the limited spatial resolution of ASCA could not conclude whether these are truly diffuse or a group of unresolved point-sources. XMM-Newton, with higher spatial resolution than ASCA, confirmed that G32.45$+$0.1 has a diffuse shell-like structure with a radius of ~ 4. The spectrum shows a featureless continuum, and can thus be fitted by a power-law model of Γ ~ 2.2 with an absorption of NH ~ 5.2 × 10²² \,cm⁻². From this NH value, we estimated the distance to G32.45$+$0.1 to be ~ 17 \,kpc. Thus, the luminosity (in the 0.5–10.0 keV band) and radius of the shell are ~ 9.5 × 10³⁴ \,ergs \,s⁻¹ and ~ 20 \,pc, respectively. The radio complex sources in the NRAO/VLA Sky Survey (NVSS; 1.4 GHz) are globally associated with the X-ray shell of G32.45$+$0.1. Therefore, G32.45$+$0.1 is likely to be a synchrotron-dominant shell-like SNR. No significant diffuse structure was found in the XMM-Newton image of another ASCA diffuse source, G38.55$+$0.0. The upper limit of the observed flux (0.5–10.0 keV) is estimated to be 9.0 × 10⁻¹³ \,ergs \,cm⁻² \,s⁻¹, which is consistent with the ASCA result.
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A 2004 study studied this question.