the exception of the cutoff rigidity (COR) of the Earth’s magnetic field. This parameter varies throughout *Suzaku’s* low Earth orbit, and larger COR constraints result in fewer particle background counts. A higher cutoff than the standard COR $>$ 4 GV has been used in previous SXRB spectral fits, and typically results in higher signal-to-noise ratio between 0.5 and 2.0 keV [@smith_etal07; @kataoka_etal15]. Here, we follow the suggested value from @smith_etal07 and use a constraint of COR $>$ 8 GV.

Since the observational goal of this study is to measure and intensities from SXRB spectra, we removed point sources from each observation before we extracted spectra. We inspected each XIS1 image for point sources to remove with self-defined region files. Observations of exceptionally bright sources (i.e., where there was clear emission extending over more than $\approx5\arcmin$), extended sources (galaxy clusters, star clusters, etc.), or other anomalous features were rejected from the data set. We also rejected any observations not taken in the standard observing window mode due to the reduction in field-of-view collecting area. For any remaining visible point sources, we defined circular exclusion regions between 1$\arcmin$ and 4$\arcmin$ in radius centered on each source. We then re-extracted the data products 