Different types of neutrinos

[Lymitra]

I just saw a documentary about the detection of neutrinos, and the first detection using chlorine atoms was able to detect only electron neutrinos which accounted for about 1/3 of the total number of neutrinos predicted. The muon and tau neutrinos weren't able to be detected by that method. My questions are:

1. Why does the sun only produce electron neutrinos?
2. Related to the above question, is it possible that the sun emits all 3 types of neutrinos, and there are in fact no neutrino oscillations?

Thanks for answering my questions.

 

[Vanadium 50]

1. The sun only produces electron-type neutrinos because the sun produces them through a process involving electrons. (That's the definition electron tyoe)

2. No, that's not possible. Partly because of reason 1, and partly because neutrino oscillations have been observed in other processes as well.

 

[Lymitra]

2. No, that's not possible. Partly because of reason 1, and partly because neutrino oscillations have been observed in other processes as well.

Thanks for your answer, and what are these other processes? I'd be curious to look them up.

 

[Vanadium 50]

Atmospheric neutrino oscillations and accelerator experiments.

 

[malawi_glenn]

and supernovae explosions :-)

 

[Vanadium 50]

I am unaware of an observation of neutrino oscillations in supernova explosions. We've seen neutrinos, but what is the evidence for oscillations?

 

[malawi_glenn]

oh, I read sloppy sometimes. Thought the discussion was about source of neutrinos ;-)

No, only neutrinos so far observed from SN's are from SN1987A so no, no evidence for oscillations from those.

 

[Meir Achuz]

1. Why does the sun only produce electron neutrinos?
2. Related to the above question, is it possible that the sun emits all 3 types of neutrinos, and there are in fact no neutrino oscillations?

1. The solar neutrinos are produced in nuclear beta decay. Muon neutrinos would have to be produced along with a muon, but the muon is too massive to be produced in nuclear beta decay. The same applies to tau neutrinos.