Top dark matter candidate loses ground to tiniest competitor.

Quote

Physicists have long searched for hypothesized dark matter particles called WIMPs. Now, focus may be shifting to the axion — an ultra-lightweight particle whose existence would solve two mysteries at once.

The ADMX experiment at the University of Washington uses a strong magnetic field to search for hypothetical dark matter particles called axions.

https://www.quantamagazine.org/why-dark-matter-might-be-axions-20191127/?utm_source=quora&utm_medium=referral

ADMX’s main magnet produces a field that’s about 150,000 times stronger than Earth’s. 

Another article on the topic (which covers more of the background): https://www.forbes.com/sites/startswithabang/2019/11/19/the-strong-cp-problem-is-the-most-underrated-puzzle-in-all-of-physics/

(I linked to the in an unrelated thread, the other day.)