South Middlesex Times

After nearly a decade of preparation, scientists, including researchers from Rutgers University, have activated a new apparatus capable of detecting a variety of mysterious tiny particles. They are in search of special subatomic particles that could potentially rewrite the physical laws of the universe.

Researchers working on the Short-Baseline Near Detector (SBND) at Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, have initiated the machine and begun detecting neutrinos produced by Fermilab’s particle accelerator beams.

Neutrinos are among the most abundant particles in the universe. About 100 trillion pass through a person’s body every second but cannot be felt due to their rare interactions with other matter. Scientists believe these particles played a vital role in the creation of the universe.

“We think neutrinos could help us get at some huge questions, like finding a more complete theory of nature at the smallest scales or even why our matter-filled universe exists at all,” said Andrew Mastbaum, an SBND team researcher and associate professor in Rutgers’ Department of Physics and Astronomy.

During construction, Associate Physics Professor Andrew Mastbaum and postdoctoral associate Ivan Lepetic expressed satisfaction with installing a device called a cosmic ray tagger. Neutrinos' rare interactions make them difficult to study, which is why scientists are particularly excited about this detector.

“Having this detector up and running is a major milestone, the culmination of a monumental international effort, and the start of an exciting chapter for the field,” Mastbaum stated.

SBND is part of Fermilab's set of particle detectors that provide information on neutrino beams created by its powerful particle accelerators. When neutrinos collide with atomic nuclei, they produce sprays of particles that physicists analyze to infer neutrino properties.

Neutrinos are among the least understood elementary particles. Previous experiments have shown puzzling behavior suggesting that current fundamental physics models may be incomplete. Neutrinos come in three types: muon, electron, and tau. Over 30 years, researchers observed anomalies hinting at another type called sterile neutrino not predicted by existing models.

“SBND is a game changer because we will get to study an enormous number of neutrino interactions, finally resolve some long-outstanding experimental mysteries and have remarkable sensitivity to potential physics phenomena beyond the Standard Model,” Mastbaum noted.

Members of SBND collaboration have been planning and constructing this detector for nearly ten years. Rutgers scientists contributed significantly to simulation software development, data analysis tools installation and startup operations.

Contributors from Rutgers include former undergraduates Andrew Schwartz ('23) and Amy Flather ('24), postdoctoral researcher Ivan Lepetic and doctoral student Keng Lin. “I am grateful to contribute to building this machine knowing that each cable I connect could help unlock secrets of the universe,” said Lin who has worked on it for months.

The detector was built by an international collaboration involving 250 physicists and engineers from Brazil, Spain, Switzerland, United Kingdom and United States. Besides searching for a fourth type of neutrino known as sterile neutrino; SBND aims to record 7,000 daily interactions—more than any other similar detector—which will allow unprecedented precision studies into these interactions informing future experiments

The initial detections mark just beginning for SBND project expected continue operating analyzing millions collected over next several years

“It isn’t every day that detector sees first detected” David Schmitz co-spokesperson SBND collaboration associate professor University Chicago stated "We’ve all spent years working toward moment first promising start search new physics"