Milky Way gamma rays may indicate dark matter

Science : Researchers think they may have detected signs of dark matter coming from the center of the Milky Way galaxy, writes Adrian Cho for Science. Because dark matter neither emits nor absorbs light, it cannot be seen directly. However, Kevork Abazajian and Manoj Kaplinghat of the University of California, Irvine, report that the Fermi Gamma-Ray Space Telescope has detected an excess of gamma rays coming from the galactic center. The excess could be produced as dark-matter particles annihilate one another. By mapping the emissions collected over a four-year period from 2008 to 2012 and fitting the data to various models, including a baseline of already-known gamma-ray sources, Abazajian and Kaplinghat found that the dark-matter hypothesis fits the data in three key ways: It has the right energy distribution, spatial distribution, and intensity. Although other sources for the gamma emissions have not been ruled out, many scientists in the field agree that the galactic center is a likely place to look for dark matter.