The results of the experiment confirm the presence of anomalies, which could indicate a new elementary particle

Experiment results confirm an anomaly that points to a new possibility in physics

Positioned deep underground on the Baksan Neutrino Observatory within the Caucasus Mountains in Russia, the finished goal of two gallium areas, left, incorporates an interior and an outer reservoir of gallium, which is irradiated by an electron neutrino supply. Credit score: AA Shikhin

The brand new scientific findings affirm an anomaly seen in earlier experiments, which can level to a brand new as-yet-confirmed elementary particle, the sterile neutrino, or level to the necessity for a brand new interpretation of a side of Normal Mannequin physics, such because the neutrino junction, measured for the primary time since 60 normal. Los Alamos Nationwide Laboratory is the lead US establishment collaborating on the Baksan Experiment on Sterile Transformations (BEST), the outcomes of which have been lately printed in journals. Bodily Evaluate Letters And the bodily overview c.

“The outcomes are very thrilling,” mentioned Steve Elliott, a senior analyst with one of many groups evaluating the information and a member of the physics division at Los Alamos. “This definitely reconfirms the anomalies we have seen in earlier experiments. However what this implies is not clear. There are actually conflicting outcomes about sterile neutrinos. If the outcomes point out that fundamental nuclear or atomic physics is misunderstood, that might be very attention-grabbing, too.” Different Los Alamos forged members Ralph Masarczyk and Inuk Kim.

Greater than a mile underground on the Baksan Neutrino Observatory within the Russian Caucasus Mountains, greatest use of 26 radioactive disks of chromium-51, a man-made radioactive isotope chromium and a 3.4 megapicurie supply of electron neutrinos, to irradiate an interior and outer tank of gallium, a tender silvery metallic was additionally utilized in earlier experiments, though it had beforehand been utilized in a single tank. The response between the electron neutrinos of chromium 51 and gallium produces the isotope germanium 71.

The measured price of manufacturing of germanium-71 was 20-24% decrease than anticipated based mostly on theoretical modeling. This discrepancy is according to anomalies seen in earlier experiments.

Experiment results confirm an anomaly that points to a new possibility in physics

An array of 26 radioactive chromium-51 discs is the supply of the electron neutrinos that work together with gallium and produce germanium-71 at charges that may be measured in opposition to anticipated charges. Credit score: AA Shikhin

BEST relies on the photo voltaic neutrino experiment, the Soviet-American Gallium Experiment (SAGE), to which Los Alamos Nationwide Laboratory was a serious contributor, starting within the late Eighties. That experiment additionally used high-density gallium and neutrino sources. Outcomes from that experiment and others indicated a deficit in electron neutrinos – a discrepancy between anticipated and precise outcomes that has come to be generally known as the “gallium anomaly”. The reason for the deficit might be proof of oscillations between an electron neutrino and sterile neutrino States.

The identical anomaly was repeated in the most effective experiment. Attainable explanations once more embrace oscillation in a sterile neutrino. Digital particle could type an vital a part of darkish matter, a doable type of matter believed to make up the overwhelming majority of the bodily universe. This interpretation might have additional testing, as a result of the measurement for every tank was almost the identical, albeit lower than anticipated.

Different explanations for the anomaly embrace the likelihood that there’s a misunderstanding within the theoretical enter to the experiment – that physics itself requires reformulation. Elliott factors out that the cross-section of the electron neutrino has not beforehand been measured at these energies. For instance, the theoretical entry for the measurement of the cross part, which is troublesome to substantiate, is the electron density within the atomic nucleus.

The experiment’s methodology was fastidiously reviewed to make sure that errors didn’t happen in features of the analysis, reminiscent of radiation supply placement or counting system operations. Future iterations of the experiment, if carried out, could embrace a unique radiation supply with greater vitality, longer half-life, and sensitivity to shorter oscillation wavelengths.


The outcomes of the NEOS experiment on sterile neutrinos differ partly from theoretical expectations


extra info:
VV Barinov et al, Outcomes of the Baksan Experiment on Sterile Transformations (BEST), Bodily Evaluate Letters (2022). DOI: 10.1103/ PhysRevLett.128.232501

VV Barinov et al, Discover electron and neutrino transitions to sterile states in the most effective experiment, bodily overview c (2022). DOI: 10.1103/ PhysRevC.105.065502

the quote: Experiment outcomes affirm anomalies, and will level to a brand new elementary particle (2022, June 16) Retrieved on June 16, 2022 from https://phys.org/information/2022-06-results-anomaly-elementary-particle.html

This doc is topic to copyright. However any truthful dealing for the aim of personal examine or analysis, no half could also be reproduced with out written permission. The content material is offered for informational functions solely.