MINERvA

Over the course of three years, scientists working on MINERvA recorded more than a million interactions of antineutrinos with other particles. This data allowed scientists to finally calculate the proton’s size using neutrinos, making this a statistically significant measurement of this characteristic.

Fermilab’s MINERvA experiment was chosen as one of the nine runners up as part of the Physics World 2023 Breakthrough of the Year. The MINERvA research shows how information about the internal structure of the proton can be gleaned from neutrinos scattering from a plastic target.

From Scientific American, March 16, 2023: Big news about a smaller size: MINERvA researchers used a new and entirely independent method to measure a proton’s radius. The team’s measurement of the proton’s radius was 0.73 femtometer, even smaller than the 0.84-femtometer electric charge radius. In either case, it is almost 10,000 times smaller than a hydrogen atom.

From Physics World, March 6, 2023: The MINERvA experiment at Fermilab has been used to study the structure of the proton using neutrinos. Teijin Cai and colleagues working on Fermilab’s MINERvA experiment have showed how information about the proton can be extracted from neutrinos that have been scattered by the detector’s plastic target.

From Science Daily, Feb. 1, 2023: Yesterday, Nature posted new research which used a beam of neutrinos for the first time to investigate the structure of protons. With Fermilab’s MINERvA detector, scientists were able to precisely measure the proton’s size and structure using neutrinos with data gathered from thousands of neutrino-hydrogen scattering events.

One of two magnetic focusing horns used in the beamline at Fermilab that produces intense neutrino beams for MINERvA and other neutrino experiments.

For the first time, particle physicists have been able to precisely measure the proton’s size and structure using neutrinos with data gathered from thousands of neutrino-hydrogen scattering events collected by MINERvA, a particle physics experiment at the U.S. Department of Energy’s Fermi National Accelerator Laboratory.

Hard to believe you can play pool with neutrinos, but certain neutrino events are closer to the game than you think. These special interactions involve a neutrino — famously elusive — striking a particle inside a nucleus like a billiard ball. MINERvA scientists study the dynamics of this subatomic ricochet to learn about the neutrino that triggered the collision. Now they have measured the probability of these quasielastic interactions using Fermilab’s medium-energy neutrino beam. Such measurements are important for current and future neutrino experiments.