Atomic effects on neutrino interactions (Paschos, Porfyriadis, G.) ν-ionization of H and noble atoms: atomic effects important for ~10keV ν-energies, but they preserve the basic features of ν-scattering off free electrons at rest. Paris December 2004 G.J. Gounaris
Basic Interaction For ~14 keV neutrinos, we cannot neglect atomic binding, Paris December 2004 G.J. Gounaris
first ν scattering off free electrons at rest << Paris December 2004 G.J. Gounaris
σ for free electrons (free electron case) < Paris December 2004 G.J. Gounaris
ν free electron spectrum very different shape! Paris December 2004 G.J. Gounaris
anti-ν free electron spectrum very different shape! Paris December 2004 G.J. Gounaris
Ionization of noble atoms (spin ind. wave functions) ( H case) binding energy Paris December 2004 G.J. Gounaris
Atomic wave functions for He, Ne, Ar, Kr, Xe RHF spin-independent wave functions (less accurate for Xe ) http://www.webelements.com/webelements Paris December 2004 G.J. Gounaris
Ne anti-ν ionization e spectra: (accuracy ~2% ) Shape analogous to the free case Paris December 2004 G.J. Gounaris
Xe anti-ν ionization e spectra: (accuracy ~10% ) Paris December 2004 G.J. Gounaris
Integrated ionization cross sections Paris December 2004 G.J. Gounaris
Binding cancels out in ratios ν flavor dep. Binding cancels out in ratios Paris December 2004 G.J. Gounaris
Binding cancels out in ratios anti-ν flavor dep. Binding cancels out in ratios Paris December 2004 G.J. Gounaris
The e-neutrino oscillation = for Paris December 2004 G.J. Gounaris
Room size experiment ! Oscillation lengths = Paris December 2004 G.J. Gounaris
An oscillation picture ~ L(m) Paris December 2004 G.J. Gounaris
Zoom at first 12m L(m) Paris December 2004 G.J. Gounaris
Weinberg angle (Dawson) The E158 SLAC Møller exp finds Paris December 2004 G.J. Gounaris
Measuring Weinberg angle 3% Best closest to source and at low Paris December 2004 G.J. Gounaris
ν e-magnetic moment There exist another two such magnetic operators. Majorana neutrinos: mm always dim=7 operators. There exist another two such magnetic operators. They induce mm not only to γ, but to Z and W also. A Paris December 2004 G.J. Gounaris
ν-electromagnetic effect (Beacom, Fayans, Wong) (if only two mass eigenstates are relevant) Look for enhancement at low ionization electron energies Paris December 2004 G.J. Gounaris
It surpasses reactors also (McLaughlin)… Zνν magnetic effect Induced incoherent contribution to Z width (operator of slide 20) Low energy neutrino ionization is surprisingly more efficient than LEP, in constraining neutrino magnetic moments! It surpasses reactors also (McLaughlin)… I have ignored Dirac neutrinos... Paris December 2004 G.J. Gounaris
Outlook If these ionization cross sections are measurable: Neutrinos at the ~10 keV-energy scale could indeed provide another way to measure Could they supply an independent measurement of the Weinberg angle at a very low energy scale? They may help improving the constraint on the neutrino magnetic moment. Paris December 2004 G.J. Gounaris