Report
Results from the Baksan Experiment on Sterile Transitions (BEST)
| العنوان: | Results from the Baksan Experiment on Sterile Transitions (BEST) |
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| المؤلفون: | Barinov, V. V., Cleveland, B. T., Danshin, S. N., Ejiri, H., Elliott, S. R., Frekers, D., Gavrin, V. N., Gorbachev, V. V., Gorbunov, D. S., Haxton, W. C., Ibragimova, T. V., Kim, I., Kozlova, Yu. P., Kravchuk, L. V., Kuzminov, V. V., Lubsandorzhiev, B. K., Malyshkin, Yu. M., Massarczyk, R., Matveev, V. A., Mirmov, I. N., Nico, J. S., Petelin, A. L., Robertson, R. G. H., Sinclair, D., Shikhin, A. A., Tarasov, V. A., Trubnikov, G. V., Veretenkin, E. P., Wilkerson, J. F., Zvir, A. I. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Nuclear Experiment, High Energy Physics - Experiment |
| الوصف: | The Baksan Experiment on Sterile Transitions (BEST) was designed to investigate the deficit of electron neutrinos, $\nu_{e}$, observed in previous gallium-based radiochemical measurements with high-intensity neutrino sources, commonly referred to as the \textit{gallium anomaly}, which could be interpreted as evidence for oscillations between $\nu_e$ and sterile neutrino ($\nu_s$) states. A 3.414-MCi \nuc{51}{Cr} $\nu_e$ source was placed at the center of two nested Ga volumes and measurements were made of the production of \nuc{71}{Ge} through the charged current reaction, \nuc{71}{Ga}($\nu_e$,e$^-$)\nuc{71}{Ge}, at two average distances. The measured production rates for the inner and the outer targets respectively are ($54.9^{+2.5}_{-2.4}(\mbox{stat})\pm1.4 (\mbox{syst})$) and ($55.6^{+2.7}_{-2.6}(\mbox{stat})\pm1.4 (\mbox{syst})$) atoms of \nuc{71}{Ge}/d. The ratio ($R$) of the measured rate of \nuc{71}{Ge} production at each distance to the expected rate from the known cross section and experimental efficiencies are $R_{in}=0.79\pm0.05$ and $R_{out}= 0.77\pm0.05$. The ratio of the outer to the inner result is 0.97$\pm$0.07, which is consistent with unity within uncertainty. The rates at each distance were found to be similar, but 20-24\% lower than expected, thus reaffirming the anomaly. These results are consistent with $\nu_e \rightarrow \nu_s$ oscillations with a relatively large $\Delta m^2$ ($>$0.5 eV$^2$) and mixing sin$^2 2\theta$ ($\approx$0.4). Comment: Paper updated to final version |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1103/PhysRevLett.128.232501 |
| URL الوصول: | http://arxiv.org/abs/2109.11482 |
| رقم الانضمام: | edsarx.2109.11482 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1103/PhysRevLett.128.232501 |
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