EXPERIMENT PERFORMED AT FERMILAB COULD LEAD US TO UNDERSTAND THE MYSTERIOUS NEUTRINOS IN A BETTER WAY

 

Neutrinos are subatomic particles that zip through the cosmos at nearly the speed of light.

(Image: © Shutterstock)

Most probably neutrinos are the most abundant fundamental particle in our universe. Billions of them will pass through your body while you read the article, but surprisingly it is highly impossible that any of them would interact with the atoms in your body. Neutrinos are basically massless (it’s matter of ongoing research, whether neutron have mass or not or if it has any mass at all what is the exact quantity) and charge less particle which do not easily interact with atoms.

Because of their undetectable nature, neutrinos are referred as ghost particles. After years of research neutrinos still remains a mystery for the physicists. First prediction about the existence of neutrino was given by Enrico fermi in 1934, but after years of research we still don’t know the exact mass of neutrino or how they change from one type to other, called neutrino oscillation (neutrino exists in nature in three flavors and they can change from one flavor to another).

To understand the neutrino oscillations physicists performed two different experiments at Fermi National laboratory. These two experiments namely – MiniBooNE (Mini Booster Neutrino Experiment) and  NOvA (NuMI Off-axis νe Appearance), helped physicists to measure the change of flavor of neutrinos with time and distance.

Intense beam of neutrinos were generated with help of particle accelerator and then the beam of neutrinos was allowed to travelled a distance of 500 miles, in case of NOvA experiment, before the bombardment of the neutrinos on carbon-12 atoms. In case of MiniBooNE experiment, the neutrinos were bombarded on carbon-12 nuclei for a very long time.

The findings of the experiments were reported in a paper published in Physics Review X journal. The experimental results are very important in understanding how neutrinos interact with atomic matters and to understand the changing of neutrinos from one flavor to another. One of the interesting findings by this experiment was that to precisely understand the interaction between neutrino and the nuclei, we need to understand the nuclear pair interaction very accurately.

Image Credit: Argonne National Laboratory

The figure shows the variation of neutrino- nucleus interaction cross-section with energy. It is quite visible that experimental result matches quite perfectly with the model based on nucleon pair interaction rather than model based on single nucleon.

Dr. Alessandro Lovato, a key member of the team of researchers, said, “while first postulated almost a century ago and first detected 65 years ago, neutrinos remain shrouded in mystery because of their reluctance to interact with matter.”

Dr. Neomi Rocco, a post-doctoral fellow from Fermi Lab said, “our team came into the picture because these experiments require a very accurate model of the interactions of neutrinos with the detector nuclei over a large energy range”.

He further added, “ours is the first approach to model these interactions at such a microscopic level, earlier approaches were not so fine grained.”

 

 Read More:

A. Lovato et al. 2020. Ab Initio Study of (νℓ,ℓ⁻) and (ν¯ℓ,ℓ⁺) Inclusive Scattering in ¹²C: Confronting the MiniBooNE and T2K CCQE Data. Phys. Rev. X 10 (3): 031068; doi: 10.1103/PhysRevX.10.031068