Potential Dark Matter Thumbprint in Galactic Center Gamma

[Schneibster]

http://www.nasa.gov/content/goddard/fermi-data-tantalize-with-new-clues-to-dark-matter/#.Uz-BRURpcnV

 

The Fermi X- and gamma-ray satellite has measured excess gamma rays from the Galactic Center of the Milky Way that cannot be explained. They are believed to be the signature of dark matter which is concentrated in the Galactic Center near the central black hole of the Milky Way. The high gravity is believed to concentrate the dark matter making the effect strong enough to be visible to our instruments in the region of the Galactic Center.

 

There is currently tension between three different experiments intended to detect dark matter in particle experiments deep underground, using instrumentation similar to that used to detect neutrinos, huge pools of water filled with particle detectors, buried miles deep in mines. Two of the experiments show probable detection; one claims to have ruled it out.

 

This new experiment detects gamma rays generated by the dark matter, from Earth orbit where they are not blocked by the atmosphere, coming from where the dark matter is concentrated in the Galactic Center, rather than trying to see signatures of individual dark matter particles in quiet caverns deep underground. And it appears to be successful: an excess of gamma rays has been detected in the expected spectrum, 1 to 3 GeV, over a region stretching some five thousand light years out along the plane of the galactic disc from the Galactic Nucleus. This in turn implies dark matter particle masses in the 30-40 GeV range. This is perhaps a third to a fifth the mass of the Higgs.

 

There is still uncertainty, in the 1-in-12 range. The signal could be false. But those are pretty good odds: 11-in-12. Ongoing investigation, and data collection, will establish the matter in other galaxies nearby in the Local Group.

Edited April 5, 2014 by Schneibster