MIT plans to build a tiny Magnetar in an attempt to detect dark matter

MIT researchers have designed an experiment that could detect hypothetical particles of dark matter known as axions. Axions are particles so small and so light that they have not yet been detected, but could axions, along with other dark matter particles potentially make up more than 80 percent of the mass in the universe. The experiment borrows from technology used in Magnetic Resonance Imaging machines.

Jesse Thaler, associate professor of physics at MIT says, “Axions are very strange, counter-intuitive particles. They’re extremely light, with feeble interactions, and yet this particle may dominate the matter budget of the universe and be five times more abundant by mass than ordinary matter. So we really had to think hard on whether these particles are in principle detectable using current technology. It’s extremely daunting.”

The experiment is called A Broadband/Resonant Approach to Cosmic Axion Detection with an Amplifying B-field Ring Apparatus, which shortens beautifully to ABRACADABRA. A series of magnetic coils are wound up in the shape of a doughnut, and placed in a superconducting fluid at a temperature just above absolute zero. A highly sensitive magnetometer at the core of the apparatus can detect the signature of an axion if it exists. An axion would produce a smaller magnetic field in the presence of the larger magnetic field produced by the the apparatus.

The design uses a fist sized instrument to simulate a Magnetar. Magnetar are extremely dense stars that pack in the mass of two or three of our Suns into a body that is less than twenty kilometers across. The MIT experiment will be looking for particles much smaller and lighter than other contemporary attempts at hunting the elusive particle. This includes the Axion Dark Matter Experiment (ADMX) at the University of Washington.