Mohamad-Ziad Charif - Antares

Figure 2.18: Flux of ν µ / ¯ν µ at the Sun’s center after production. The mass ofthe WIMP used here is 200 GeV. A comparison can be seen between the threechannels b¯b, τ + τ − , W + W − and between ν µ and ¯ν µ flux.nels b¯b, τ + τ − , W + W − . It is immediately clear that the b channel is soft with thespectrum peaking at very small values of z (z =E νM WIMP) and diminishing at largervalues. The W channel on the other hand seem to be very hard as the spectrum isalmost constant for all values of z. Finally the τ channel is hard as well but thespectrum starts to fall when the energy of the neutrino is 80% of the mass of theWIMP. However, for smaller values it is roughly constant.Neutrino interactionThe neutrino interaction will be described in the next chapter. While the descriptionis based for rock and sea water (Earth), the underlying physics is the same forneutrino interactions in the Sun.Neutrino oscillationsThe principle of neutrino oscillations scenario is related to the idea that the neutrinoleptonic flavor eigenstates are not the same as the neutrino mass eigenstates.This leads to a mixing scenario where the flavor eigenstate becomes a linear combinationof those of the mass. This oscillation scenario has been verified experimentallyby several experiments such as Super-kamiokande[78, 79], SNO[80],K2K[81], and other.29