Galactic Puzzles in the Gamma-Ray Sky

Studies of data from the Fermi Gamma-Ray Space Telescope have revealed surprising excesses of apparently diffuse gamma-ray emission toward the heart of the Milky Way, including the giant structures known as the Fermi Bubbles and the central glow often called the Galactic Center Excess. I will outline these signals and their properties. The latter excess in particular has garnered great interest as a possible signal of either dark matter particles colliding and annihilating, or a previously undiscovered population of pulsars in the stellar bulge. Analyses of the photon statistics of this excess have been used to argue that the pulsar interpretation is strongly favored -- however, I will present recent work arguing that it may be premature to exclude a dark matter origin for the excess on these grounds. I will outline the history of our understanding of the excess and the arguments for various interpretations, describe the current status of the controversy, and discuss future paths forward.

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Meeting ID: 981 3481 4135

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