Constraining Astrophysical Neutrino Flavor Composition from Leptonic Unitarity

Abstract

The recent IceCube observation of ultra-high-energy astrophysical neutrinos has begun the era of neutrino astronomy. In this work, using the unitarity of leptonic mixing matrix, we derive nontrivial unitarity constraints on the flavor composition of astrophysical neutrinos detected by IceCube. Applying leptonic unitarity triangles, we deduce these unitarity bounds from geometrical conditions, such as triangular inequalities. These new bounds generally hold for three flavor neutrinos, and are independent of any experimental input or the pattern of leptonic mixing. We apply our unitarity bounds to derive general constraints on the flavor compositions for three types of astrophysical neutrino sources (and their general mixture), and compare them with the IceCube measurements. Furthermore, we prove that for any sources without ${\nu }_{\tau }$ neutrinos, a detected ${\nu }_{\mu }$ flux ratio $<1/4$ will require the initial flavor composition with more ${\nu }_e$ neutrinos than ${\nu }_{\mu }$ neutrinos.

arXiv commentJCAP Final Version. 24pp. Only minor refinements, references added

References in corpus (50)

• Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector
• Observation of High-Energy Astrophysical Neutrinos in Three Years of IceCube Data
• Mass and Flavor Mixing Schemes of Quarks and Leptons
• Detecting Tau Neutrino Oscillations at PeV Energies
• Detecting Nutau Oscillations as PeV Energies
• Status of three-neutrino oscillation parameters, circa 2013
• Unitarity of the Leptonic Mixing Matrix
• Measuring Flavor Ratios of High-Energy Astrophysical Neutrinos
• Flavor Composition and Energy Spectrum of Astrophysical Neutrinos
• Decay of High-Energy Astrophysical Neutrinos
• TeV Scale Inverse Seesaw in SO(10) and Leptonic Non-Unitarity Effects
• Effects of neutrino mixing on high-energy cosmic neutrino flux
• Cosmic Neutrino Pevatrons: A Brand New Pathway to Astronomy, Astrophysics, and Particle Physics
• Natural TeV-Scale Left-Right Seesaw for Neutrinos and Experimental Tests
• Limit on the diffuse flux of ultra-high energy tau neutrinos with the surface detector of the Pierre Auger Observatory
• Neutrino Decays over Cosmological Distances and the Implications for Neutrino Telescopes
• New Limits on the Ultra-high Energy Cosmic Neutrino Flux from the ANITA Experiment
• Neutrino Observatories Can Characterize Cosmic Sources and Neutrino Properties
• Leptonic Unitarity Triangle and CP-violation
• Sensitivity to ${\theta }_{13}$ and $\delta$ in the Decaying Astrophysical Neutrino Scenario
• Simplified Unitarity Triangles for the Lepton Sector
• On the flavor composition of the high-energy neutrino events in IceCube
• Flavor Ratios of Astrophysical Neutrinos: Implications for Precision Measurements
• Unitarity triangles and geometrical description of CP violation with Majorana neutrinos
• The Glashow resonance at IceCube: signatures, event rates and $pp$ vs. $p\gamma$ interactions
• Measuring the 13-mixing angle and the CP phase with neutrino telescopes
• Testing neutrino flavor mixing plus decay with neutrino telescopes
• How astrophysical neutrino sources could be used for early measurements of neutrino mass hierarchy and leptonic CP phase
• Implications of Leptonic Unitarity Violation at Neutrino Telescopes
• Standard Model Explanation of the Ultra-high Energy Neutrino Events at IceCube
• Flavor Composition of UHE Neutrinos at Source and at Neutrino Telescopes
• An Analysis of Cosmic Neutrinos: Flavor Composition at Source and Neutrino Mixing Parameters
• Neutrino Oscillation and CP Violation
• Neutrino flux ratios at neutrino telescopes: The role of uncertainties of neutrino mixing parameters and applications to neutrino decay
• Towards Determination of the Initial Flavor Composition of Ultrahigh-energy Neutrino Fluxes with Neutrino Telescopes
• Neutrino Telescopes as a Probe of Broken $\mu$-$\tau$ Symmetry
• Neutrino Mixing and Neutrino Telescopes
• Interplay of energy dependent astrophysical neutrino flavor ratios and new physics effects
• Leptonic Unitarity Triangles in Matter
• Neutrino mixing scenarios and AGN
• On Probing theta_{23} in Neutrino Telescopes
• IceRay: An IceCube-centered Radio-Cherenkov GZK Neutrino Detector
• Diffuse Ultra-High Energy Neutrino Fluxes and Physics Beyond the Standard Model
• Cosmic Neutrino Flavor Ratios with Broken ${\nu }_{\mu }-{\nu }_{\tau }$ Symmetry
• Connecting Leptonic Unitarity Triangle to Neutrino Oscillation
• On Leptonic Unitary Triangles and Boomerangs
• Dirac Lepton Angle Matrix v.s. Majorana Lepton Angle Matrix and Their Renormalization Group Running Behaviours
• Flavor revolution at ICECUBE horizons?
• Constructing the Leptonic Unitarity Triangle
• Probing Neutrino Flavor Transition Mechanism with Ultra High Energy Astrophysical Neutrinos

Cited by in corpus (20)

• The Giant Radio Array for Neutrino Detection (GRAND): Science and Design
• Theoretically palatable flavor combinations of astrophysical neutrinos
• Testing decay of astrophysical neutrinos with incomplete information
• Spectral analysis of the high-energy IceCube neutrinos
• Inferring the flavor of high-energy astrophysical neutrinos at their sources
• A Possible Two-component Flux for the High Energy Neutrino Events at IceCube
• The Future of High-Energy Astrophysical Neutrino Flavor Measurements
• Astrophysical neutrinos flavored with Beyond the Standard Model physics
• Analysis of the 4-year IceCube high-energy starting events
• Universe's Worth of Electrons to Probe Long-Range Interactions of High-Energy Astrophysical Neutrinos
• Flavor of cosmic neutrinos preserved by ultralight dark matter
• Echo Technique to Distinguish Flavors of Astrophysical Neutrinos
• High-energy neutrino fluxes and flavor ratio in the Earth's atmosphere
• Unitarity Bounds of Astrophysical Neutrinos
• Aspects of the Flavor Triangle for Cosmic Neutrino Propagation
• Probing New Physics at Future Tau Neutrino Telescopes
• Flavors of Astrophysical Neutrinos with Active-Sterile Mixing
• The flavor composition of ultra-high-energy cosmic neutrinos: measurement forecasts for in-ice radio-based EeV neutrino telescopes
• Connecting Leptonic Unitarity Triangle to Neutrino Oscillation with CP Violation in Vacuum and in Matter
• Two-detector flavor sensitivity to ultra-high-energy cosmic neutrinos