Space-time propagation of neutrino wave packets at high temperature and density

Abstract

We study the space-time evolution of ``flavor'' neutrino wave-packets at finite temperature and density in the early Universe prior to BBN. We implement non-equilibrium field theory methods and linear response to study the space-time evolution directly from the effective Dirac equation in the medium. There is a rich hierarchy of time scales associated with transverse and longitudinal dispersion and coherence. A phenomenon of ``freezing of coherence'' is a result of a competition between longitudinal dispersion and the separation of wave-packets of propagating modes in the medium. Near a resonance the coherence and oscillation time scales are enhanced by a factor $1/\sin 2\theta$ compared to the vacuum. Collisional relaxation via charged and neutral currents occurs on time scales much shorter than the coherence time scale and for small vacuum mixing angle, shorter than the oscillation scale. Assuming that the momentum spread of the initial wave packet is determined by the large angle scattering mean free path of charged leptons, we find that the transverse dispersion time scale is the shortest and is responsible for a large suppression in both the survival and transition probabilities on time scales much shorter than the Hubble time. For small mixing angle the oscillation time scale is \emph{longer} than the collisional relaxation scale. The method also yields the evolution of right-handed wave packets. Corrections to the oscillation frequencies emerge from wave-packet structure as well as from the energy dependence of mixing angles in the medium.

arXiv commentreferences corrected, version to appear in PRD

References in corpus (38)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• First Results from KamLAND: Evidence for Reactor Anti-Neutrino Disappearance
• Measurement of Neutrino Oscillation with KamLAND: Evidence of Spectral Distortion
• Leptogenesis for Pedestrians
• Leptogenesis as the origin of matter
• Neutrino Emission from Neutron Stars
• Neutrinos in cosmology
• Cosmological bounds on neutrino degeneracy improved by flavor oscillations
• Dissipation via Particle Production in Scalar Field Theories
• Neutrino Interactions in Hot and Dense Matter
• The Neutrino Mass Window for Baryogenesis
• Oscillations of neutrinos and mesons in quantum field theory
• Analytic and Numerical Study of Preheating Dynamics
• Analytical treatment of neutrino asymmetry equilibration from flavour oscillations in the early universe
• Stringent Constraints on Cosmological Neutrino-Antineutrino Asymmetries from Synchronized Flavor Transformation
• On the Treatment of Neutrino Oscillations Without Resort to Weak Eigenstates
• Coherence of neutrino oscillations in the wave packet approach
• Absolute Values of Neutrino Masses: Status and Prospects
• Some Aspects of Thermal Leptogenesis
• Neutrino Wave Packets in Quantum Field Theory
• Coherence Effects in Neutrino Oscillations
• High-energy neutrino conversion and the lepton asymmetry in the universe
• The field-theoretical approach to coherence in neutrino oscillations
• Coherence and Wave Packets in Neutrino Oscillations
• Coherence of neutrino flavor mixing in quantum field theory
• Neutrino Physics
• Asymptotic Dynamics in Scalar Field Theory: Anomalous Relaxation
• Neutrino Propagation in Dense Astrophysical Systems
• Flavor and chiral oscillations with Dirac wave packets
• Dirac Spinors and Flavor Oscillations
• Cosmological Implications of Neutrinos
• Lepton Numbers in the framework of Neutrino Mixing
• Oscillations of neutrinos produced and detected in crystals
• Fermion Damping in a Fermion-Scalar Plasma
• Damping Rates and Mean Free Paths of Soft Fermion Collective Excitations in a Hot Fermion-Gauge-Scalar Theory
• Neutrino Oscillations in the Early Universe: A Real Time Formulation
• Neutrino wave function and oscillation suppression
• Additional time-dependent phase in the flavor-conversion formulas

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