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.   
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G.J. Gounaris

2. Basic Interaction
For ~14 keV neutrinos, we cannot neglect atomic binding,
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G.J. Gounaris

3. first ν scattering off free electrons at rest
<<
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4. σ for free electrons (free electron case) < Paris December 2004
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5. ν free electron spectrum
very different shape!
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G.J. Gounaris

6. anti-ν free electron spectrum
very different shape!
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G.J. Gounaris

7. Ionization of noble atoms
(spin ind. wave functions)
( H case)
binding energy
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G.J. Gounaris

8. Atomic wave functions for He, Ne, Ar, Kr, Xe
RHF spin-independent wave functions (less accurate for Xe )
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G.J. Gounaris

9. Ne anti-ν ionization e spectra:
(accuracy ~2% )
Shape analogous to the free case
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G.J. Gounaris

10. Xe anti-ν ionization e spectra:
(accuracy ~10% )
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G.J. Gounaris

11. Integrated ionization cross sections
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12. Binding cancels out in ratios
ν flavor dep.
Binding cancels out in ratios
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G.J. Gounaris

13. Binding cancels out in ratios
anti-ν flavor dep.
Binding cancels out in ratios
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G.J. Gounaris

14. The e-neutrino oscillation=
for
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15. Room size experiment ! Oscillation lengths = Paris December 2004
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16. An oscillation picture~
L(m)
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17. Zoom at first 12m
L(m)
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18. Weinberg angle (Dawson) The E158 SLAC Møller exp finds
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19. Measuring Weinberg angle3%
Best closest to source and at low
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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
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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
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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