New research shows that dark matter has a different distribution in our galaxy than previously thought, and that advances dark matter’s status as a potential source of the observed gamma ray excess in the Milky Way’s center. High-resolution simulations reveal that the dark matter distribution in the inner galaxy is not spherical, but flattened and asymmetrical. The findings confirm the theory that the gamma ray excess is due to dark matter annihilation.

Scientists have long suspected dark matter annihilation to be a source of these rays, but the rays’ spatial spread did not match the arrangement of dark matter they had predicted. Another theory argues that ancient millisecond pulsars could produce the rays.

For the new study published in Physical Review Letters, researchers modeled the formation of Milky Way-like galaxies under environmental conditions similar to those of Earth’s cosmic neighborhood, thereby reproducing simulated Milky Way-like galaxies that bear strong resemblance to the real thing.