# Matter Altering Neutrinos

1. Aug 13, 2004

What do people think of the idea that the type of matter a neutrino passes through can affect it's probability of being a certain flavour/colour.

eg, through rock it is more likley to be one colour,
through air it is more likley to be another colour.

2. Aug 13, 2004

### jtolliver

Neutrinos dont have a color. I don't see any reason the flavor should depend on the material its passing through.

3. Aug 13, 2004

neutrinos do not interact with mass. Electron neutrinos, tau neutrinos and muon neutrinos are all non interacting neutrinos that pass through matter with no effect. Maybe one neutrino in a billion will interact and this interaction will be very small.

4. Aug 14, 2004

### ArmoSkater87

Neutrinos interact only with the weak forces, which is why they dont interact much at all. Since they have no charge, they cannot interact with the electromagnetic fields, nor with strong forces. They are said to interact slightly with electrons. The first detector that was built to detect neutrinos used heavy water as a way of detecting them. When a neutrino would hit the deterium, the neutron would be transformed into a proton and separate from the hydrogen (also a proton). This in turn would release a flash of light which can be detected using photo-multiplier tubes (PM tubes). I believe that this kind of detection only works for electron neutrinos, but doesnt work for muon or tau neutrinos. Out of a whole day of detecting using that detector, only about 5 or 10 neutrinos interacted to cause a flash of light.

5. Aug 14, 2004

this is not the firs neutrino detector. The first one was build usin a large tank of $${C_2}{Cl_4}$$
the neutrinos would come into the tank and interact with the cleaning fluid by making radioactive Argon atoms in the tank. This is how they measured how many neutrinos passed though. The heavy water neutrino test came a lot later.

6. Aug 14, 2004

### LURCH

And if I recall correctly from my (admittedly shallow) researching of the "neutrino paradox", results from both detectors agree with the idea that neutrinos fluctuate randomly, and the chances of detecting one in any of the three states is roughly equal;1/3. This would seem to suggest that the type of material used to detect a neutrino does not effect the probability of that neutrino being in any one of the three potential states.

Far from conclusive, but it's the only evidence we have, AFAIK.

7. Aug 14, 2004

### ArmoSkater87

Alrite, agreed. Although i dont see how Argon could in any way be "radioactive"...its a nobel gas with not such a large atomic number.

Last edited: Aug 14, 2004
8. Aug 14, 2004

### ArmoSkater87

I believe you recall correctly. I recall something similar...scientists were detecting 1/3 of what they expected, which lead them to believe that they were detecting only one of the 3 flavors.