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Rob Hoff
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When the Z boson is around can a neutrino interact with a particle other than an electron? And how does the neutrino find the electron if the neutrino is neutral and does not interact electromagnetically?
Matterwave said:A neutrino interacts via the weak interactions. An electron neutrino interacts with electrons, a muon neutrino interacts with muons, a tau neutrino interacts with tau (this is how the flavor states are defined).
Orodruin said:All types of neutrinos may interact with electrons through weak interactions via the exchange of a Z boson. The flavor states are relevant only for amplitudes containing the exchange of W bosons. An example of this can be found in the interaction rates of solar neutrinos which are typically detected in one of three ways:
Charged current interactions: Basically ##\nu_x + d \to e^- + u##, may only occur for x = e. The measured flux is around a third of that expected from the standard solar model (SSM).
Neutral current interactions: ##\nu_x + D \to p + n + \nu_x##, mediated by Z exchange and measured in heavy water by the SNO collaboration. May occur for any neutrino flavor x with the same cross section up to loop corrections. The measured flux is that expected from the SSM.
Elastic scattering: ##\nu_x + e^- \to \nu_x + e^-##, as measured by Super-Kamiokande etc. The neutrino may be of any flavor. However, the cross section for ##\nu_e## is higher due to the additional possibility of exchanging a W boson in addition to the basic diagram with Z boson exchange. The measured flux lies between the CC and NC rates (as expected).
The Z boson does not care about the flavor - that's why experiments looking for neutral current interactions (and elastic scattering) are sensitive to all three types with a comparable sensitivity.Matterwave said:The interactions with inter-flavors are highly suppressed even compared to the already low interaction cross sections present for neutrinos. For example, the MSW effective Hamiltonian in the flavor basis has only basically 1 element at the electron-electron neutrino flavor sector due to the fact that there are only electrons, and no muons or tau in the solar environment.
All this has nothing to do with the electromagnetic interaction.And how does the neutrino find the electron if the neutrino is neutral and does not interact electromagnetically?
mfb said:The Z boson does not care about the flavor - that's why experiments looking for neutral current interactions (and elastic scattering) are sensitive to all three types with a comparable sensitivity.
mfb said:What do you mean with "getting rid"? You might get less events if you are not sensitive to it.
On the other hand, for solar muon and tau neutrinos, the energy is not sufficient for charged current interactions anyway.
Orodruin said:Matterwave: The reason NC interactions to not appear in the MSW Hamiltonian is that they are equal (up to loop effects of ##\mathcal O(10^{-5})## times the CC contribution). The NC part of the MSW Hamiltonian is therefore essentially proportional to the unit matrix and only contributes to the neutrino flavor evolution with an overall phase. It is therefore customary to drop this contribution and only work with the CC contribution. This is no longer true when dealing with sterile neutrino flavors where the NC part is proportional to the projection operator onto the active states.
Edit: Relatively recent open accessreview on matter effects in neutrino oscillations: http://dx.doi.org/10.1155/2013/972485
The relevant discussion is on pages 2 and 3.
Carter: Your post goes against the last 52 years of research in neutrino physics (the muon neutrino was discovered in 1962). It is possible you have seen analogies of neutrino oscillations to spin precession (the mathematics is the same), but these are simply analogies. Neutrino oscillations are fundamentally based upon and our currently only confirmation of different neutrinos having different masses.
James Carter said:It is possible that there are no Neutrino Flavors at all; the different Flavors all have the same speed and therefore the same mass. It may be that the observation of change in Neutrino Flavors due to weak interactions with other Leptons is simply the Neutrino changing the direction of its spin to correspond to that of the other Lepton; meaning that the [itex]\upsilon[/itex]e, [itex]\upsilon[/itex][itex]\mu[/itex], and [itex]\upsilon[/itex][itex]\tau[/itex] are all corrisponding Neutrino particles
Please give references for your claims. Personal theories are not allowed here.James Carter said:The sum of the masses of the Neutrinos is .320+/-.081 eV; since the three Neutrinos have different masses that would dictate that, when one of the three Neutrinos comes within a distance of 10-16 of a meter of either a Muon, Electron, or Tau particle, weak interactions between the two particles would cause the speed of the Neutrino to change and therefore the mass, subsequently, would change.
Neutrinos interact with the Z boson through the weak nuclear force. This interaction is known as the neutral current interaction, where the Z boson is exchanged between the neutrino and a fermion, such as an electron or quark.
Yes, neutrinos can also interact with other particles through the weak force. They can interact through both charged current interactions, where a W boson is exchanged, and neutral current interactions, where a Z boson is exchanged.
Neutrino interactions with electrons are unique because electrons are the only particles that are leptons, while neutrinos are also leptons. This means that neutrinos can interact with electrons through both charged current and neutral current interactions.
Yes, neutrino interactions can produce a variety of particles, including muons, taus, and quarks. These particles can be produced through both charged current and neutral current interactions, depending on the type of neutrino and the energy of the interaction.
Studying neutrino interactions can provide valuable insights into fundamental particles and forces in the universe. Neutrinos are the most abundant particles in the universe, and understanding their interactions can help us better understand the structure of matter, the origins of the universe, and potential new physics beyond the Standard Model.