New data weaken link between rare, energetic particles and giant black holes
DENVER — New data cast doubt on the origin of high-energy cosmic rays, which previous evidence indicated came mostly from galaxies that house supermassive black holes.
An investigation of more of the rare, energetic events suggests that fewer than half may come from this type of galaxy, David Thomas of Colorado State University in Fort Collins reported May 3 at a meeting of the American Physical Society.
High-energy cosmic rays are charged particles, such as protons, that smash into Earth’s atmosphere packing as much punch as a fast-pitch baseball. Researchers for years have puzzled over the origin of these rare, unusually energetic particles.
Two years ago, astronomers working at the world’s biggest cosmic ray observatory, the 3,000-square-kilometer Pierre Auger Observatory in Malargüe, Argentina, reported that these energetic cosmic rays come from regions of the sky coinciding with the location of galaxies known to house giant black