Hunting for dark matter with massive magnets and haloscopes

Jan. 23 (UPI) -- Scientists at the Institute for Basic Science in Seoul, South Korea, have designed powerful magnets to hunt for the axion, a theoretical particle that could be a component of dark matter.

The majority of the cosmos is made up of dark matter and dark energy. Unlike visible matter, dark matter doesn't emit light or absorb radiation, making it nearly impossible to detect. Scientists have yet to observe dark matter directly.

But scientists believe dark matter is -- like visible matter -- organized into large superstructure within the universe. They also believe dark matter is made up of tiny particles, like the axion.

Scientists have indirectly observed the presence of axions by measuring X-ray emission irregularities as solar particles pass through Earth's magnetic field. When an axion passes through a large magnetic field, it can interact with a photon and become converted into another photon.

Researchers are trying to recreate this scenario in the lab using super powerful magnets and image the phenomenon using a haloscope.

"In simple terms, you can image the resonant cavity as a cylinder, like a soft drink can, where the energy of the photons generated from the axions-photons interaction is amplified," Byeong Rok Ko, a scientists at the IBS Center for Axion and Precision Physics Research, explained in a news release.

Ko and his colleagues are experimenting with different types of magnets to ensure the signature of the axion-to-photon conversion isn't drowned out and lost in the noise of the high energy experiments.

"Magnets are the most important feature of the haloscope, and also the most expensive," Ko said. "While other experiments seeking to detect dark matter around the world use solenoid magnets, we are the first to try to use toroidal magnets. Since it has never been used before, you cannot easily buy the equipment, so we develop it ourselves."

Before researchers can detect the evidence of the axion-to-photon conversion, they have to predict -- through theoretical math and physics -- exactly what that conversion will look like amid a mess of electromagnetic data.

Researchers have previously theorized the expression of an axion conversion can't be easily predicted within the chaotic energies created a toroidal shaped magnet. The latest research by Ko and his colleagues -- published this week in the journal Physical Review D -- suggests the opposite.

The findings are a promising step in the path towards detecting an axion-to-photon conversion.