Study Makes Substantial Leap Forward in Quest for Dark Matter

Dr. Noble is the Canadian principal investigator on PICO. He explains that the novel detection limits will aid narrow the focus of future detection efforts and will guide the design of future studies that will offer greater sensitivity and a greater likelihood of dark matter identification.

“We are extremely excited about such results,” says Dr. Noble. “Not only have we established a novel world-leading limit for dark matter interactions, but we have also illustrated that with sufficient controls the bubble chamber technology can be run free of backgrounds that could mimic the signal. This bodes very well for the future as the association is poised to launch a novel tonne scale detector based on this technology. This novel detector, dubbed PICO 500, will have an order of magnitude greater physics capability and will enhance a vast swathe of the parameter space predicted by dark matter theories.”

The PICO-60 study is presently the world’s biggest bubble chamber in operation. It is filled with 45 litres of octafluoropropane – a target flud employed to detect WIMP interactions. The detector maintains the target fluid in a superheated state such that, when dark matter particles interact with the fluorine in the fluid, the ever so slight energy deposit triggers the fluid to begin to rapidly boil at that location and prepares a bubble in the chamber.

Cameras and acoustic sensors around the chamber observe the bubble formation and evolution, and are employed to enhance the ability to distinguish between possible dark matter interactions and other background sources when analysing the data.

“Queen’s studies have long been at the cutting edge of discoveries in the field of particle astrophysics,’ says John Fisher, Acting Vice-Principal at Queen’s. “Such finding by the PICO study continues to reflect that leadership and represents a huge leap forward in the hunt for the most elusive matter in our universe.”

Queen’s University is home to Arthur McDonald, co-recipient of the 2015 Nobel Prize in Physics for his revolutionary research in neutrinos, as well as Gilles Gerbier, the Canada Excellence Research Chair in Particle Astrophysics. The study announced today continues a legacy of scientific breakthroughs and world-leading research that has cemented Queen’s reputation at the forefront of the field.

In 2016, the Canada First Research Excellence Fund offered Queen’s with a vita; investment to support the creation of the Canadian Particle Astrophysics Research Centre. The centre will help trigger a number of leading-edge projects, comprising the current and future upgrades to the PICO study, which will enable Queen’s and its partner institutions to continue on this trajectory of study excellence.