Improved measurement of solar neutrinos from the Carbon-Nitrogen-Oxygen cycle by Borexino and its implications for the Standard Solar Model

Abstract

We present an improved measurement of the CNO solar neutrino interaction rate at Earth obtained with the complete Borexino Phase-III dataset. The measured rate R${}_{\mathrm{CNO}}$ = $6.7_{-0.8}^{+2.0}$ counts/(day$\cdot$ 100 tonnes), allows us to exclude the absence of the CNO signal with about 7$\sigma$ C.L. The correspondent CNO neutrino flux is $6.6_{-0.9}^{+2.0}\times 10^8$ cm${}^{-2}$ s${}^{-1}$, taking into account the neutrino flavor conversion. We use the new CNO measurement to evaluate the C and N abundances in the Sun with respect to the H abundance for the first time with solar neutrinos. Our result of $N_{\mathrm{CN}}$ = $(5.78_{-1.00}^{+1.86})\times 10^{-4}$ displays a $\sim$2$\sigma$ tension with the "low metallicity" spectroscopic photospheric measurements. On the other hand, our result used together with the ${}^7$Be and ${}^8$B solar neutrino fluxes, also measured by Borexino, permits to disfavour at 3.1$\sigma$ C.L. the "low metallicity" SSM B16-AGSS09met as an alternative to the "high metallicity" SSM B16-GS98.

8 pages, 6 figures

References in corpus (8)

• The fate of hints: updated global analysis of three-flavor neutrino oscillations
• The chemical make-up of the Sun: A 2020 vision
• Measurement of the solar neutrino capture rate with gallium metal. III: Results for the 2002--2007 data-taking period
• A new Generation of Standard Solar Models
• Experimental evidence of neutrinos produced in the CNO fusion cycle in the Sun
• Observational constraints on the origin of the elements. IV: The standard composition of the Sun
• Testing the statistical compatibility of independent data sets
• CN-Cycle Solar Neutrinos and Sun's Primordial Core Metalicity

Cited by in corpus (23)

• Direct detection of dark matter: a critical review
• Final results of Borexino on CNO solar neutrinos
• Higher metal abundances do not solve the solar problem
• Solar neutrino physics
• Solar fusion III: New data and theory for hydrogen-burning stars
• Ab initio informed evaluation of the radiative capture of protons on ${}^7$Be
• Axion Helioscopes as Solar Thermometers
• Constraints on the properties of macroscopic transport in the Sun from combined lithium and beryllium depletion
• Theoretical and Experimental Challenges in the Measurement of Neutrino Mass
• ${\beta }^{-}$ decay $Q$-value measurement of ${}^{136}$Cs and its implications to neutrino studies
• Fluorescence emission of the JUNO liquid scintillator
• Observation of low-lying isomeric states in ${}^{136}$Cs: a new avenue for dark matter and solar neutrino detection in xenon detectors
• Borexino's search for low-energy neutrinos associated with gravitational wave events from GWTC-3 database
• Performance of the 1-ton Prototype Neutrino Detector at CJPL-I
• Novel techniques for alpha/beta pulse shape discrimination in Borexino
• Solar Models and Astrophysical S-factors Constrained by Helioseismic Results and Updated Neutrino Fluxes
• CYG$\nu$S: Detecting solar neutrinos with directional gas time projection chambers
• Hunting Nonstandard Neutrino Interactions and Leptoquarks in Dark Matter Experiments
• Study on U/Th residual radioactivity in acrylic from surface treatment
• Testing the dark side of neutrino oscillations with the solar neutrino fog at Dark Matter experiments
• The impact of the transport of chemicals and electronic screening on helioseismic and neutrino observations in solar models
• Using Lithium and Beryllium to Study Structure and Evolution of Rotating Stars
• Solar Model Independent Constraints on the Sterile Neutrino Interpretation of the Gallium Anomaly