The Solar and Atmospheric Neutrino Anomalies

The solar and atmospheric neutrino anomalies have been described as one of the greatest scientific puzzles of our time. Perplexed scientists have noticed that only half the amount of electron neutrinos our sun produces are being detected. Initially, it was feared that this may have meant that our sun was slowly being extinguished (since this number of neutrinos is less than necessary to produce the amount of energy emitted), but the neutrino deficit has remained constant; thus, this possibility has been ruled out. It has also been noted that when cosmic rays collide with the Earth's atmosphere, electron and muon neutrinos are produced; however, there appears to be a deficit of muon neutrinos. Furthermore, this neutrino deficit demonstrates directional dependence (there are twice as many neutrinos coming downward than through the Earth), thus suggesting that muon neutrinos are oscillating into less detectable neutrinos. Several theories propose that neutrinos oscillate between the three neutrino “families.” This could help to explain the solar and atmospheric neutrinos enigmas. Another interesting theory is the neutrino-mirror matter theory which proposes that neutrinos not only oscillate between different neutrino families (or flavours), but also into mirror neutrinos.


	The Solar and Atmospheric Neutrino Anomalies The solar and atmospheric neutrino anomalies have been described as one of the greatest scientific puzzles of our time. Perplexed scientists have noticed that only half the amount of electron neutrinos our sun produces are being detected. Initially, it was feared that this may have meant that our sun was slowly being extinguished (since this number of neutrinos is less than necessary to produce the amount of energy emitted), but the neutrino deficit has remained constant; thus, this possibility has been ruled out. It has also been noted that when cosmic rays collide with the Earth's atmosphere, electron and muon neutrinos are produced; however, there appears to be a deficit of muon neutrinos. Furthermore, this neutrino deficit demonstrates directional dependence (there are twice as many neutrinos coming downward than through the Earth), thus suggesting that muon neutrinos are oscillating into less detectable neutrinos. Several theories propose that neutrinos oscillate between the three neutrino “families.” This could help to explain the solar and atmospheric neutrinos enigmas. Another interesting theory is the neutrino-mirror matter theory which proposes that neutrinos not only oscillate between different neutrino families (or flavours), but also into mirror neutrinos. The oscillation between neutrinno families, demonstrated in the above diagram. Dreaming Of A Mirror Universe \| What is Mirror Matter? \| What are Neutrinos? \| The Solar and Atmospheric Neutrino Anomalies \| Nature's Four Forces \| The Detection of Mirror Matter \| How Will These Theories Affect our Lives? \| Did You Know...? \| Conclusion \| Bibliography \| Acknowledgements \| Related Links