Victor B. Semikoz

Cornering solar radiative-zone fluctuations with KamLAND and SNO salt

We update the best constraints on fluctuations in the solar medium deep within the solar radiative zone to include the new SNO salt solar neutrino measurements. We find that these new measurements are now sufficiently precise that neutrino-oscillation parameters can be inferred independently of any assumptions about fluctuation properties. Constraints on fluctuations are also improved, with amplitudes of 5% now excluded at the 99% confidence level for correlation lengths in the range of a few hundred kilometres. Because they are sensitive to correlation lengths which are so short, these solar neutrino results are complementary to constraints coming from helioseismology.

Neutrino conversions in a polarized medium

Electron polarization induced by magnetic fields can modify the potentials relevant for describing neutrino conversions in media with magnetic fields. The magnitudes of polarization potentials are determined for different conditions. We show that variations of the electron polarization along the neutrino trajectory can induce resonant conversions in the active-sterile neutrino system, but cannot lead to level crossing in the active-active neutrino system. For neutrino flavour conversions the polarisation leads only to a shift of the standard MSW resonance. For polarizations � < ∼ 0.04 the direct modifications of the potential (density) due to the magnetic field pressure are smaller than the modifications due to the polarization effect. We estimate that indeed the typical magnitude of the polarization in the sun or in a supernova are not expected to exceed 10 −2 . However even such a small polarization may lead to interesting consequences for supernova physics and for properties of neutrino signals from collapsing stars.

Confronting spin flavor solutions of the solar neutrino problem with current and future solar neutrino data

A global analysis of spin flavor precession (SFP) solutions to the solar neutrino problem is given, taking into account the impact of the full set of latest solar neutrino data, including the recent SNO data and the 1496-day Super-Kamiokande data. These are characterized by three effective parameters:

The simplest resonant spin-flavour solution to the solar neutrino problem

\ensuremath{\Delta}{m}_{\mathrm{SOL}}^{2}\ensuremath{\equiv}\ensuremath{\Delta}{m}^{2},

Magnetic field instability in a neutron star driven by the electroweak electron-nucleon interaction versus the chiral magnetic effect

the neutrino mixing angle

Large Mixing Angle Oscillations as a Probe of the Deep Solar Interior

{\ensuremath{\theta}}_{\mathrm{SOL}}\ensuremath{\equiv}\ensuremath{\theta},

Neutrino annihilation in hot plasma

and the magnetic field parameter

Large-Scale Magnetic Field Generation by alpha Effect Driven by Collective Neutrino-Plasma Interaction

\ensuremath{\mu}{B}_{\ensuremath{\perp}}.

Lepton asymmetry growth in the symmetric phase of an electroweak plasma with hypermagnetic fields versus its washing out by sphalerons

For the last we adopt a self-consistent magnetohydrodynamics field profile in the convective zone and identify an optimum

Resonant origin for density fluctuations deep within the Sun: helioseismology and magneto-gravity waves

{B}_{\ensuremath{\perp}}\ensuremath{\sim}80\mathrm{kG}