Suzaku X-ray Observations of the Fermi Bubbles: Northernmost Cap and Southeast Claw Discovered with MAXI-SSC

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We report on Suzaku observations of large-scale X-ray structures possibly related with the Fermi Bubbles obtained in 2013 with a total duration of 80 ks. The observed regions were the: (i) northern cap (N-cap; l 0 deg, 45 deg < b < 55 deg) seen in the Mid-band (1.7-4.0 keV) map recently provided by MAXI-SSC and (ii) southeast claw (SE-claw; l 10 deg, -20 deg < b < -10 deg) seen in the ROSAT all-sky map and MAXI-SSC Low-band (0.7-1.7 keV) map. In each region, we detected diffuse X-ray emissions which are represented by a three component plasma model consisting of an unabsorbed thermal component (kT 0.1 keV) from the Local Bubble, absorbed kT = 0.30+/-0.05 keV emission representing the Galactic Halo, and a power-law component due to the isotropic cosmic X-ray background radiation. The emission measure of the GH component in the SE-claw shows an excess by a factor of 2.5 over the surrounding emission at 2 deg away. We also found a broad excess in the 1.7-4.0 keV count rates across the N-cap after compiling other archival data from Suzaku and Swift. The spectral stacking analysis of the N-cap data indicates the presence of another thermal component with kT = 0.70 (+0.22,-0.11) keV. The temperature of kT 0.3 keV of the Galactic Halo is higher than the ubiquitous value of kT 0.2 keV near the Fermi Bubbles, and can be even higher (0.7 keV). We discuss our findings in the context of bubble-halo interaction.