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arXiv · 2210.10884

Inference finds consistency between a neutrino flavor evolution model and Earth-based solar neutrino measurements

Caroline Laber-Smith·A. A. Ahmetaj·Eve Armstrong·A. Baha Balantekin·Amol V. Patwardhan·M. Margarette Sanchez·Sherry Wong
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Abstract

We continue examining statistical data assimilation (SDA), an inference methodology, to infer solutions to neutrino flavor evolution, for the first time using real - rather than simulated - data. The model represents neutrinos streaming from the Sun's center and undergoing a Mikheyev-Smirnov-Wolfenstein (MSW) resonance in flavor space, due to the radially-varying electron number density. The model neutrino energies are chosen to correspond to experimental bins in the Sudbury Neutrino Observatory (SNO) and Borexino experiments, which measure electron-flavor survival probability at Earth. The procedure successfully finds consistency between the observed fluxes and the model, if the MSW resonance - that is, flavor evolution due to solar electrons - is included in the dynamical equations representing the model.

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Caroline Laber-Smith, A. A. Ahmetaj, Eve Armstrong, A. Baha Balantekin, Amol V. Patwardhan, M. Margarette Sanchez, Sherry Wong. 2022-10-19. Inference finds consistency between a neutrino flavor evolution model and Earth-based solar neutrino measurements. https://doi.org/10.1103/physrevd.107.023013

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