Experiment results confirm discrepancy, could point to new elementary particle

Scientific results confirm loopholes in previous experiments pertaining to the new fundamental particle, sterile neutrino, or suggest the need for a new explanation of an aspect of standard model physics such as neutrino cross section first computed 60 years ago.

The results of the study undertaken by Los Alamos National Laboratory is published in the journal Physical Review Letters and Physical Review C.

The results are exciting, and definitely reaffirm the loopholes observed in previous experiments. But what is observed now is not obvious. This has led to contradictory results about sterile neutrinos.

It would be interesting if the results indicate atomic physics or fundamental nuclear physics are misunderstood.

For the experiment part, at a depth of more than a mile under the ground at Baksan Neutrino Observatory, the researchers used an artificial radioisotope of chromium, 26 illuminated disks of chromium 51, and 3.4 megacurie base of electron neutrinos to light up an outer and inner tank of gallium. The reaction between electron neutrinos from gallium and chromium 51 produces the isotope germanium 71.

The rate of production of germanium 71 was 20 -24% lesser than expected based on theoretical modelling. The discrepancy observed is in line with the loophole observed in previous experiments.

Meanwhile, Baksan Experiment on Sterile Transitions builds on a solar neutrino experiment named the Soviet-American Gallium Experiment that started in the late 1980s. The experiment used high intensity neutrinos sources and gallium.

The results of this experiment and others indicated a shortfall of electron neutrinos – a difference between actual results and predicted results that came to be known as gallium anomaly.

An interpretation of deficit could be evidence for oscillations between sterile neutrinos states and electron neutrino.