The study has lent more conclusive insights into the composition of Dark Matter, by eliminating the possibility of particles called axions
For several decades now, astronomers have been making frantic attempts to uncover the mystery that is dark matter. Despite the substance making up more than 85% of the universe, there is very little knowledge regarding its behavior or composition. Dark matter is invisible in nature, however, it can be detected by the weak interactions it has with other forms of matter. Scientists have spent a considerable amount of time, and resources, to understand this form of matter. Now, in a new study, a team of astronomers from the Massachusetts Institute of Technology (MIT), have ruled out the possibility of axions constituting dark matter, the strongest contender particle till now.
While scientists have not been able to directly identify what constitutes dark matter, they have resorted to ruling out possible particles instead. ‘Dark Photons’ were ruled out earlier, by the HADES particle detector. Some other Weakly-Interacting Massive Particles (WIMPs) have also been eliminated over previous studies. The scientific community has long suspected axions to be a major part of dark matter composition.
To test this theory, the researchers conducted an experiment, which they have dubbed ABRACADABRA (A Broadband/Resonant Approach to Cosmic Axion Detection with an Amplifying B-field Ring Apparatus). Magnetic fields cease to exist within a ring, in conventional physics. However the presence of axions in the ring, could trigger a weak response in the detectors. To test this, they made use of small magnet, enclosed in a chamber, at a temperature of absolute zero (0 K/ -273°c), suspended from a string, and enclosed in superconducting materials to rule out interference.
However, the team failed to detect any axions in the multiple mass ranges, which they tested. They plan to continue tests in other mass ranges, and with improved apparatus, which can detect weaker interactions as well.