Scientists at the Fermi National Accelerator Laboratory (Fermilab) have identified the first neutrino interactions at the Short-Baseline Near Detector (SBND). This marks a significant milestone for the SBND collaboration, which has been developing the detector for nearly a decade. “It isn’t every day that a detector sees its first neutrinos,” said David Schmitz, co-spokesperson for the SBND collaboration and associate professor of physics at the University of Chicago.
“We’ve all spent years working toward this moment, and this first data is a very promising start to our search for new physics.”
The SBND, part of Fermilab’s Short-Baseline Neutrino (SBN) Program, will play a crucial role in addressing long-standing anomalies in neutrino experiments. These experiments have observed inconsistencies in the number and type of neutrinos detected at different distances from a neutrino source. The Standard Model, despite being a well-tested theory, does not fully explain certain observed phenomena.
Over the past 30 years, multiple experiments have suggested the possible existence of a new type of neutrino beyond the known three — muon, electron, and tau neutrinos — that may not interact through the weak nuclear force. Fermilab scientist Anne Schukraft speculated, “That could mean that there are more than the three known neutrino flavors. Unlike the three known kinds of neutrinos, this new type of neutrino wouldn’t interact through the weak force.
The only way we would see them is if the measurement of the number of muon, electron, and tau neutrinos does not add up as it should.”
The SBN Program, featuring both near and far detectors, aims to investigate these anomalies with unprecedented detail.
First neutrinos discovery at SBND
While ICARUS began collecting data in 2021, SBND is expected to provide a wealth of new information by capturing about 7,000 neutrino interactions daily.
A critical aspect of SBND’s mission includes understanding neutrino interactions with argon. While simpler nuclei like helium and hydrogen are relatively easy to model, argon’s complex 40-nucleon composition presents a greater challenge. “We will collect 10 times more data on how neutrinos interact with argon than all previous experiments combined,” said Fermilab scientist and SBND co-spokesperson Ornella Palamara.
“The analyses we conduct will also be very important for DUNE.”
In addition to neutrinos, the detector may also detect other particles produced by the particle beam. “There could be things, outside of the Standard Model, that have nothing to do with neutrinos but are produced as a byproduct of the beam that the detector would be able to see,” explained Schukraft. This includes the potential detection of lightweight dark matter particles, which could offer insights into the “dark sector” mysteries.
The successful detection of the first neutrinos marks the beginning of a new era for the SBND collaboration. They will continue to operate the detector and analyze the substantial volume of data collected over the next several years. “Seeing these first neutrinos is the start of a long process that we have been working towards for years,” Palamara concluded.
“This moment is the beginning of a new era for the collaboration.”
April Isaacs is a news contributor for DevX.com She is long-term, self-proclaimed nerd. She loves all things tech and computers and still has her first Dreamcast system. It is lovingly named Joni, after Joni Mitchell.
