A Search for Periodicities in the $^8$B Solar Neutrino Flux Measured by the Sudbury Neutrino Observatory

TL;DR

This study analyzed four years of Sudbury Neutrino Observatory data to search for periodic variations in the $^8$B solar neutrino flux, finding only the expected annual modulation due to Earth's orbit and no other significant periodicities.

Contribution

It provides the first comprehensive search for sinusoidal periodicities in the $^8$B neutrino flux over a broad period range using multiple analysis methods.

Findings

Detected annual modulation consistent with Earth's orbital eccentricity

No significant periodicities between 1 day and 10 years found

Results do not support previous claims of 7% flux modulation

Abstract

A search has been made for sinusoidal periodic variations in the $^8$B solar neutrino flux using data collected by the Sudbury Neutrino Observatory over a 4-year time interval. The variation at a period of one year is consistent with modulation of the $^8$B neutrino flux by the Earth's orbital eccentricity. No significant sinusoidal periodicities are found with periods between 1 day and 10 years with either an unbinned maximum likelihood analysis or a Lomb-Scargle periodogram analysis. The data are inconsistent with the hypothesis that the results of the recent analysis by Sturrock et al., based on elastic scattering events in Super-Kamiokande, can be attributed to a 7% sinusoidal modulation of the total $^8$B neutrino flux.