Interpreting the LSND anomaly: sterile neutrinos or CPT-violation or...?

Abstract

We first study how sterile neutrinos can fit the 5sigma bar-nu_mu --> bar-nu_e LSND anomaly: 2+2 solutions are strongly disfavoured by solar and atmospheric data, while 3+1 solutions can still give a poor fit (for a specific range of oscillation parameters, to be tested by MiniBooNE). If instead MiniBoone will find no nu_mu --> nu_e signal, we will have a hint for CPT violation. Already now, unlike sterile neutrinos, CPT-violating neutrino masses can nicely accomodate all safe and unsafe data. We study how much CPT must be conserved according to atmospheric and K2K data and list which CPT-violating signals could be discovered by forthcoming solar and long-baseline experiments.

12 pages. Version 2: update about SNO. Version 3: addendum about KamLAND. Version 4: addendum at pages 11,12 discussing how much the recent WMAP data disfavour the 3+1 sterile solution

References in corpus (7)

• Matter Effects in Upward-Going Muons and Sterile Neutrino Oscillations
• Constraining neutrino physics with BBN and CMBR
• Frequentist analyses of solar neutrino data (updated including KamLAND and SNO data)
• 4-Neutrino mass schemes and the likelihood of (3+1)-mass spectra
• Cornering (3+1) sterile neutrino schemes
• Super-Kamiokande atmospheric neutrinos: Status of subdominant oscillations
• Which solar neutrino experiment after KamLAND and Borexino?

Cited by in corpus (89)

• Phenomenology with Massive Neutrinos
• Sterile Neutrino Oscillations: The Global Picture
• Theory of Neutrinos: A White Paper
• Physics at a future Neutrino Factory and super-beam facility
• Sterile neutrino oscillations after first MiniBooNE results
• Cosmology seeking friendship with sterile neutrinos
• A combined analysis of short-baseline neutrino experiments in the (3+1) and (3+2) sterile neutrino oscillation hypotheses
• Probing oscillations into sterile neutrinos with cosmology, astrophysics and experiments
• Progress in the physics of massive neutrinos
• Light sterile neutrinos
• See-Saw Energy Scale and the LSND Anomaly
• Status of atmospheric neutrino(mu)<-->neutrino(tau) oscillations and decoherence after the first K2K spectral data
• Thermalisation of light sterile neutrinos in the early universe
• Short-Baseline Active-Sterile Neutrino Oscillations?
• Explaining LSND by a decaying sterile neutrino
• Leptonic CP violation studies at MiniBooNE in the (3+2) sterile neutrino oscillation hypothesis
• Neutrino Phenomenology of Very Low-Energy Seesaws
• Probing the LSND scale and four neutrino scenarios with a neutrino telescope
• Lorentz and CPT Invariance Violation In High-Energy Neutrinos
• Measuring Active-to-Sterile Neutrino Oscillations with Neutral Current Coherent Neutrino-Nucleus Scattering
• Testing New Physics Explanations of MiniBooNE Anomaly at Neutrino Scattering Experiments
• A model of CPT violation for neutrinos
• Short-Baseline Electron Neutrino Disappearance, Tritium Beta Decay and Neutrinoless Double-Beta Decay
• Impact of eV-mass sterile neutrinos on neutrino-driven supernova outflows
• Sterile neutrinos, lepton asymmetries, primordial elements: how much of each?
• Searching for eV-scale sterile neutrinos with eight years of atmospheric neutrinos at the IceCube neutrino telescope
• CPT Violation and Decoherence in Quantum Gravity
• Damping signatures in future neutrino oscillation experiments
• CPT Violating Decoherence and LSND: a possible window to Planck scale Physics
• Mirror model for sterile neutrinos
• Detecting sterile neutrinos with KATRIN like experiments
• Neutrino Mass and New Physics
• Status of the CPT Violating Interpretations of the LSND Signal
• MiniBooNE and LSND data: non-standard neutrino interactions in a (3+1) scheme versus (3+2) oscillations
• Quantum decoherence and neutrino data
• LSND anomaly from CPT violation in four-neutrino models
• Sterile Neutrinos and Light Dark Matter Save Each Other
• Light Sterile Neutrinos: Status and Perspectives
• Exploring a Non-Minimal Sterile Neutrino Model Involving Decay at IceCube and Beyond
• Late Time Neutrino Masses, the LSND Experiment and the Cosmic Microwave Background
• Extrinsic CPT Violation in Neutrino Oscillations in Matter
• Unsolved problems in particle physics
• Constraining Mass Spectra with Sterile Neutrinos from Neutrinoless Double Beta Decay, Tritium Beta Decay and Cosmology
• Confronting mass-varying neutrinos with MiniBooNE
• Implications of a Massless Neutralino for Neutrino Physics
• MINOS and CPT-violating neutrinos
• Neutrinos Have Mass - So What?
• Neutrino Physics: Open Theoretical Questions
• Hint of CPT Violation in Short-Baseline Electron Neutrino Disappearance
• WMAPping out Neutrino Masses
• Can a CPT Violating Ether Solve ALL Electron (Anti)Neutrino Puzzles?
• LSND versus MiniBooNE: Sterile neutrinos with energy dependent masses and mixing?
• CPT Tests: Kaon vs Neutrinos
• Short-Baseline Electron Neutrino Disappearance at a Neutrino Factory
• A Three-Flavor, Lorentz-Violating Solution to the LSND Anomaly
• Probing New Physics by Comparing Solar and KamLAND Data
• Neutrino Masses in Astroparticle Physics
• Short-Baseline antinu_mu -> antinu_e Oscillations
• Short-baseline Neutrino Oscillation Waves in Ultra-large Liquid Scintillator Detectors
• CPT violating neutrinos in the light of KamLAND and Super-K
• Searching for New Physics in Future Neutrino Factory Experiments
• The solar neutrino puzzle: present situation and future scenarios
• Atmospheric neutrinos as a probe of eV^2-scale active-sterile oscillations
• Testing CPT Symmetry with Supernova Neutrinos
• Probing CPT violation with atmospheric neutrinos
• Neutrinos in a Sterile Throat
• Common Radiative Origin of Active and Sterile Neutrino Masses
• Active-sterile neutrino mixing in the absence of bare active neutrino mass
• Neutrino Physics
• More General BBN Constraints on Neutrino Oscillations Parameters - Relaxed or Strengthened
• Last CPT-Invariant Hope for LSND Neutrino Oscillations
• A Reanalysis of the LSND Neutrino Oscillation Experiment
• Theory of Neutrino Masses and Mixings
• Indirect Dark Matter Detection in the Light of Sterile Neutrinos
• Symmetry breaking, and the effect of matter density on neutrino oscillation
• Neutrinos and the Phenomenology of CPT Violation
• Neutrino Factory R&D
• Neutrino Properties and Tests of Symmetries
• Nucleon decay in gauge unified models with intersecting D6-branes
• Astrophysical and Cosmological Neutrinos
• eV Seesaw with Four Generations
• Light Sterile Neutrinos in the Supersymmetric U(1)' Models and Axion Models
• CPT invariance and neutrino physics
• Sterile neutrino decay and the LSND experiment
• Sterile Neutrinos in astrophysical and cosmological sauce
• Searches for sterile neutrinos (and other light particles)
• Testing CPT Invariance with Neutrinos
• EUROnu-WP6 2010 Report
• Neutrino Oscillations Due to Nonuniversal Gauge Interactions in the Weak Sector