DF | Home | Seminari e Convegni

The Galactic Center Gamma-Ray Excess has a spectrum, angular distribution, and overall intensity that agree remarkably well with that expected from annihilating dark matter particles in the form of an approximately 50 GeV thermal relic. Previous claims that these photons are clustered on small angular scales or trace the distribution of known stellar populations once appeared to favor interpretations in which this signal originates from a large population of unresolved millisecond pulsars. More recent work, however, has overturned these conclusions, finding that the observed gamma-ray excess does not contain discernible small-scale power, and is distributed with approximate spherical symmetry, not tracing any known stellar populations. In light of these results, it now appears significantly more likely that the Galactic Center Gamma-Ray Excess is produced by annihilating dark matter.

Bio: Dan Hooper, professor of physics at University of Wisconsin–Madison, is a particle astrophysicist and cosmologist specializing in dark matter, neutrino astronomy, gamma-ray astronomy, and cosmic ray physics. He is the author of several books, including Dark Cosmos: In Search of our Universe’s Missing Mass and Energy (2006), Nature’s Blueprint: Supersymmetry and the Search for a Unified Theory of Matter and Force (2008), At the Edge of Time: Exploring the Mysteries of Our Universe’s First Seconds (2019), and Particle Cosmology and Astrophysics (2024). He also co-hosts the podcast Why This Universe?. In September 2024, he became the director of Wisconsin IceCube Particle Astrophysics Center (WIPAC).