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arXiv · 1906.10980

The gallium anomaly revisited

Joel Kostensalo·Jouni Suhonen·Carlo Giunti·Praveen C. Srivastava
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Abstract

The gallium anomaly, i.e. the missing electron-neutrino flux from $^{37}$Ar and $^{51}$Cr electron-capture decays as measured by the GALLEX and SAGE solar-neutrino detectors, has been among us already for about two decades. We present here a new estimate of the significance of this anomaly based on cross-section calculations using nuclear shell-model wave functions obtained by exploiting recently developed two-nucleon interactions. The gallium anomaly of the GALLEX and SAGE experiments is found to be smaller than that obtained in previous evaluations, decreasing the significance from 3.0$\sigma$ to 2.3$\sigma$. This result is compatible with the recent indication in favor of short-baseline $\bar\nu_{e}$ disappearance due to small active-sterile neutrino mixing obtained from the combined analysis of the data of the NEOS and DANSS reactor experiments.

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Joel Kostensalo, Jouni Suhonen, Carlo Giunti, Praveen C. Srivastava. 2019-06-26. The gallium anomaly revisited. https://doi.org/10.1016/j.physletb.2019.06.057

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