Download presentation
Presentation is loading. Please wait.
1
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
2
Basic Interaction For ~14 keV neutrinos, we cannot neglect atomic binding, Paris December 2004 G.J. Gounaris
3
first ν scattering off free electrons at rest
<< Paris December 2004 G.J. Gounaris
4
σ for free electrons (free electron case) < Paris December 2004
G.J. Gounaris
5
ν free electron spectrum
very different shape! Paris December 2004 G.J. Gounaris
6
anti-ν free electron spectrum
very different shape! Paris December 2004 G.J. Gounaris
7
Ionization of noble atoms
(spin ind. wave functions) ( H case) binding energy Paris December 2004 G.J. Gounaris
8
Atomic wave functions for He, Ne, Ar, Kr, Xe
RHF spin-independent wave functions (less accurate for Xe ) Paris December 2004 G.J. Gounaris
9
Ne anti-ν ionization e spectra:
(accuracy ~2% ) Shape analogous to the free case Paris December 2004 G.J. Gounaris
10
Xe anti-ν ionization e spectra:
(accuracy ~10% ) Paris December 2004 G.J. Gounaris
11
Integrated ionization cross sections
Paris December 2004 G.J. Gounaris
12
Binding cancels out in ratios
ν flavor dep. Binding cancels out in ratios Paris December 2004 G.J. Gounaris
13
Binding cancels out in ratios
anti-ν flavor dep. Binding cancels out in ratios Paris December 2004 G.J. Gounaris
14
The e-neutrino oscillation
= for Paris December 2004 G.J. Gounaris
15
Room size experiment ! Oscillation lengths = Paris December 2004
G.J. Gounaris
16
An oscillation picture
~ L(m) Paris December 2004 G.J. Gounaris
17
Zoom at first 12m L(m) Paris December 2004 G.J. Gounaris
18
Weinberg angle (Dawson) The E158 SLAC Møller exp finds
Paris December 2004 G.J. Gounaris
19
Measuring Weinberg angle
3% Best closest to source and at low Paris December 2004 G.J. Gounaris
20
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
21
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
22
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
23
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
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.