Widespread Detection of Two Components in the Hot Circumgalactic Medium of the Milky Way

Abstract Surrounding the Milky Way (MW) is circumgalactic medium (CGM), an extended reservoir of hot gas that has significant implications for evolution MW. We used HaloSat all-sky survey to study CGM’s soft X-ray emission in order better define its distribution and structure. extend a previous southern CGM (Galactic latitude b < ?30°) include northern ( > 30°) find evidence at least two model components different temperatures are required produce observed emission. The cooler component typical temperature kT ?0.18 keV, while hotter ?0.7 keV. measure both warm wide range (?0.005–0.03, ?0.0005–0.004 cm ?6 pc, respectively), indicating clumpy. A patch relatively consistent was found north, allowing spectrum be studied finer detail using stacked spectrum. well described with including = 0.166 ± 0.005 keV 0.69 ? 0.05 + 0.04 As alternative adding component, neon-enhanced single-temperature also tested have worse fit statistics poor residuals.