New Analysis Suggests Potential Dark Matter Signal from Fermi Telescope Data
Observations of galactic movement and the cosmic microwave background reveal that approximately 85% of the matter in the universe is “dark,” meaning it doesn’t interact with light and isn’t composed of known elementary particles. Physicists have been searching for the constituents of this dark matter, proposing various hypothetical particles. Recent analysis of data from the Fermi Space Telescope may offer a new clue.
An astrophysicist, Tomonori totani of the University of Tokyo, has identified a potential signal consistent with dark matter in Fermi’s data. The analysis suggests the dark matter particles could have a mass around 500 times that of a proton. This mass aligns with a leading dark matter candidate: weakly interacting massive particles (WIMPs).
WIMPs are theorized to annihilate each other upon collision, releasing high-energy gamma radiation. Previous observations with Fermi in 2008 detected gamma radiation from the center of the Milky Way that initially appeared to be this annihilation signal. Though, researchers determined this radiation could also be attributed to numerous neutron stars present in the galactic center.
To address this ambiguity, Totani focused his analysis on regions of the sky with fewer suspected neutron stars - specifically, the halo of the Milky Way, away from the galactic center and the dense star disk. Analyzing 15 years of data from Fermi’s LAT telescope, he found a meaningful excess of gamma radiation between 2 and 200 giga-electron volts, peaking at 20 giga-electron volts.This energy distribution matches predictions for the gamma radiation produced by WIMP annihilation.
Totani describes the finding as “possible” evidence for dark matter, and potentially the first direct observation of it. Confirmation would also indicate that dark matter is comprised of particles beyond those described in the Standard Model of particle physics.
However, Totani emphasizes the need for independent verification of his results by other research groups.Even with confirmation, the source of the gamma excess must be definitively established, as unkown astrophysical phenomena could potentially be responsible.He suggests further investigation by searching for similar gamma radiation patterns in dwarf galaxies, where different conditions could help isolate a true dark matter signal.