Data analyses by Drexel University and the implementation of machine learning tools by TU Dortmund University were critical to identifying high-energy neutrinos, their direction and energy reconstruction for the Milky Way. This work allowed the team to retain over an order of magnitude more neutrino events, resulting in an analysis that was three times more sensitive than previous searches.
The dataset used in the study included 60,000 neutrinos spanning 10 years of IceCube data — 30 times as many events as the team had used in previous analyses.
“Over the past four to five years, it’s clear that the data analysis techniques are just better,” Seckel said. “We’re improving what we can do and what we can learn. This applies not just to IceCube, but to the use of machine learning and artificial intelligence in general. These tools are incredibly important and relevant. The people getting their graduate degrees from IceCube institutions are going off into the broader marketplace.”
Digging deeper into the data
But exactly where are those neutrinos coming from in the Milky Way?
“It’s difficult to be able to narrow it to one source or another yet,” Seckel said. “There’s a large black hole at the center of the galaxy, but this central engine is not tremendously active at the moment.”
With the application of new data science techniques, the IceCube Collaboration is likely to have the answer soon.
After all, who wouldn’t want to know how and where a “ghost” particle got blasted into space?
For Axani, he’s intrigued by the conundrum of neutrinos being the most abundant particles in the universe, yet humanity’s ability to detect so few of them so far.
“We have to develop these behemoth detectors to even see them,” Axani said. “This research allows us to probe the fundamental properties of our Universe. So far, neutrinos are the only particle to point to physics beyond the Standard Model, the basic building blocks of the universe. Digging deeper requires very interesting science and cool technology, and we’re all about that.”
The IceCube Collaboration, with over 350 scientists in 58 institutions from around the world, runs an extensive scientific program that has established the foundations of neutrino astronomy. Its research efforts, including critical contributions to the detector operation, are funded by agencies in Australia, Belgium, Canada, Denmark, Germany, Italy, Japan, New Zealand, Republic of Korea, Sweden, Switzerland, Taiwan, the United Kingdom, and the United States, including the National Science Foundation.
Article by Tracey Bryant, with resources from IceCube Collaboration
Photos courtesy of Spencer Axani
June 29, 2023