Can Oscillations Explain Neutrino Anomalies?

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SUMMARY

The discussion centers on the solar and atmospheric neutrino deficits, where fewer neutrinos are detected on Earth than expected from solar nuclear processes and atmospheric interactions. Neutrino oscillation is proposed as a solution, explaining the "missing" neutrinos by their transformation into different types. The SNOL experiment confirmed the expected number of neutrinos, while recent experiments like T2K, NOvA, and OPERA have measured the appearance of different neutrino flavors, supporting the oscillation theory. However, anomalies from the LSND and MiniBooNE experiments remain contentious, with multiple studies contradicting their findings.

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  • Understanding of neutrino physics and oscillation theory
  • Familiarity with experimental methods in particle physics
  • Knowledge of cross-section measurements in neutrino interactions
  • Awareness of recent neutrino experiments such as T2K and NOvA
NEXT STEPS
  • Research the SNOL experiment and its findings on solar neutrinos
  • Explore the T2K and NOvA experiments for neutrino flavor appearance
  • Study the implications of the LSND and MiniBooNE anomalies in neutrino physics
  • Investigate cosmological constraints on sterile neutrinos and their implications
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Physicists, researchers in particle physics, and students studying neutrino interactions and oscillation phenomena will benefit from this discussion.

  • #31
No, I just tried to keep it simple
 
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  • #32
So, you don't do a calculation but guess at an answer. and when your guess doesn't match reality, it's not that your guess is wrong, it's that neutrino oscillations are a bad theory.

I am unconvinced.
 
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  • #33
Not at all, I am just trying to understand the concept, I did not mean to ruffle your feathers
 
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  • #34
A Majeski said:
I would expect the Solar deficit to be closer to 1/2 or something other than 2/3. This value indicates that the dispersion of three neutrino flavors is basically flat regardless of the detectors proximity to a large neutrino source, like the Sun.
This is wrong. The mechanism at work here is the Mikheev-Smirnov-Wolfenstein effect and adiabatic flavor transitions. The MSW matter effect on oscillations imply that neutrinos exit the Sun almost entirely in the second mass eigenstate (provided that they are energetic enough to be produced above resonance). This in turn means that the nu_e survival probability is based almost exclusively on the nu_e content of that mass eigenstate.

It is also wrong that only two flavors are involved. Theory predicts almost equal numbers of mu and tau neutrinos.

It is not the case that oscillations equilibrate the flavors. The oscillation probabilities depend on several things, including the mixing parameters.

A Majeski said:
also, it seems to me that the neutrino mass change should progress from lightest to heaviest with an accompanied decrease in speed. It should not progress from heaviest to lightest as this would require the speed to increase, I cannot see any example where this occurs in other phenomenon.
This is well known (assuming fixed momentum) and it does not really affect oscillations until wave packets of different mass eigenstates separate which would just average out the oscillations. This does happen for solar neutrinos but as mentioned they effectively only consist of one mass eigenstate anyway so it is not super relevant.

Note: Neutrinos will not change their speed during propagation. They are in a quantum mechanical superposition of their mass states and it is the mass states that move at different velocities.

A Majeski said:
Not at all, I am just trying to understand the concept, I did not mean to ruffle your feathers
You’re not though. You are making assumptions of how things behave and try to draw conclusions based on those (faulty) assumptions. That will never end well and you will not really learn anything. What you should be doing if you wish to understand is to pick up some reference literature on the subject. For example, section III.G of this review.
 
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