Researchers have successfully conducted the first search for axions as part of the ORGAN (Oscillating Resonant Group AxioN) experiment. Conducted by scientists at the University of Western Australia’s (UWA) Quantum Technologies and Dark Matter Laboratory, the ORGAN experiment aims to decipher the mystery behind dark matter. It is designed to search for dark matter and is Australia’s first contribution to the cause. The results of the experiment will come in handy in conducting future searches, according to the researchers.  

Scientists carried out four years of research and development to complete the first search for axions. Looking for axions is crucial in the search for dark matter as they are promising candidates for the matter.

According to Aaron Quiskamp, PhD student at UWA, the results of the first search have helped narrow down the search for dark matter and rule out the popular theory about their nature. “We performed the most sensitive search so far for axion dark matter in a particular mass range,” he added.

Admitting that they could zero in on an axion dark matter, Quiskamp said it was still exciting to conduct the experiment, which is Australia’s first large-scale and long-term dark matter detection experiment.

He added that it also gave them an insight into axion dark matter and the results would come in handy in conducting future searches.

Highlighting the significance of the ORGAN experiment, Dr Ben McAllister, a physicist at the Australian Research Council Centres of Excellence for Engineered Quantum Systems and Dark Matter Particle Physics, said they are trying to aim their search at potential candidates and eliminate the ones that are less likely to be correct.

“Because we don’t know how heavy the axion is, if it even exists, we need multiple experiments searching the different mass ranges predicted by the theory,” McAllister added. Notably, the experiment is the first to use a type of detector called axion haloscope in that mass range.

Explaining the use of haloscope, McAllister said it was employed to detect dark matter by converting it into photons. “When we don’t see any little flashes, as was the case this time, we instead place exclusion limits, where we rule out axions that our experiment would have been sensitive to,” McAllister added. Following this, McAllister said, they abandon the search for dark matter in that mass and move to a different mass.