World's most sensitive lab-based axion search presents its first results

This article presents the first results from the ALPS II experiment, a highly sensitive search for axions, hypothetical particles proposed to explain dark matter and other cosmological mysteries. Led by Axel Lindner at DESY Research Centre in Germany, the collaboration found no evidence of axions during this initial campaign but their results provide crucial guidance for future research.

The axion is a light particle that interacts very weakly with ordinary matter, making it challenging to detect. The ALPS II experiment generates axions in a lab and detects them by converting them back into light. This approach differs from other dark matter searches that assume conditions from the early universe. The ALPS II setup uses a laser beam and strong magnetic fields to convert photons into axions and then back to light, which can be detected as a faint beat signal.

The experiment's sensitivity has been significantly improved through the addition of 12 superconducting magnets and an optical cavity, making it 12 orders of magnitude more sensitive than previous experiments. Despite finding no axion evidence, the ALPS II experiment was 20 times more sensitive to axions than previous attempts. The collaboration plans further upgrades to boost sensitivity even more, potentially bringing the search closer to detecting axions and providing crucial insights into dark matter.