outermost region.

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Resonance Scattering in the Central Region
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In Figure 7, we show the spectra in the 0–2’and 2–4’ regions. In the spectrum of the 0–2’ region, the fit residual has a negative line feature around 0.85 keV. This feature disappears in the 2–4’ region and other outer regions (Figure 3). This is possibly due to resonance scattering of the Fe ${\rm_{XV\hspace{-.1em}I\hspace{-.1em}I}}$ line, which was reported with the RGS (Xu et al. 2002; Werner et al. 2009). When we introduce a negative gaussian line in the spectral model, the fit significantly improves with a F-test probability of $<0.01$%. In that case, the Fe abundance increases by 15%. We compared the XIS result in the central region with that using the RGS and looked into whether the features are consistent. We modeled the XIS spectrum with two BREMSS for the continuum thermal emission from the plasma and the LMXBs, and add each emission line with a gaussian. The temperatures of these BREMSS models are fixed to 0.642 keV and 7.0 keV for the thermal and LMXB emission, respectively. The former is the best-fit vAPEC temperature in table 3. The 