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CERN: Neutrino beam is 1000x more powerful than the sun!
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My apologies to those who have already seen this. I thought it deserved its own thread...
Were you aware that many particle accelerators, especially CERN, have the capability to produce very powerful neutrino beams? Did you know that they actually send these beams through the earth to neutrino detectors stationed hundreds of miles away? Everyone seems to be worried about the energies of particles colliding in the LHC but to me, the real worry may be the neutrino beam and what it might be doing to the Earth.
A little background (skip to conclusion if you don't want to read all the details)...
What is a neutrino?
Neutrinos (more precisely, anti-neutrinos) were postulated by Pauli as a means of preserving the conservation of energy involved in the beta-decay of a neutron:
n ---> p+ + e- + v-e*
where v-e* is the symbol for the electron anti-neutrino. It is a neutral, almost massless particle that carries away some of the energy when a neutron decays into a proton and an electron.
The solar furnace produces electron neutrinos by fusion of protons in its core according to the following reaction:
p+ + p+ ---> 4-He + e- + v-e
where v-e is the symbol for the electron neutrino.
Due to it's small size and absence of electric charge, the neutrino is very difficult to detect at low energies because it hardly interacts with matter. However, as the energy goes up, the probability of neutrinos interacting with matter goes up as well (note that this does not necessarily imply that the probability of detecting neutrinos goes up - it depends on how you are looking for them).
Neutrino flavors
The electron has higher energy analogs known as the muon and tau lepton. These particles can decay into an electron by emitting correspondingly higher energy neutrinos. The reactions are:
u ---> e- + v-u + v-e*
tau ---> e- + v-tau + v-e*
where u is the muon and v-u is the muon-neutrino; and tau is the tau lepton and v-tau is the tau-neutrino. The energies of naturally produced neutrinos rank as v-e < v-mu < v-tau.
As early as the 1960s experiments were setup to detect neutrinos emitted from the sun. Due to the low energy of the solar neutrinos, the detectors had to be absolutely huge. They were typically located deep underground to shield the effects of cosmic rays. The detectors consisted of huge tanks filled with a chlorinated organic liquid. When a neutrino struck one of the chlorine atoms in the tank, it converted it to argon gas, which could be very accurately measured. However, these detectors and variations thereof could only detect the lowest energy electron neutrinos coming from the sun. The results of every experiment revealed that the flux of electron neutrinos from the sun was only a fraction of that predicted by the solar model. This left scientists scratching their heads for many years.
Neutrino oscillation
In an attempt to explain the shortfall of electron neutrinos coming from the sun, a theory was proposed that allowed the flavor of neutrinos to oscillate as they pass through matter. According to this theory, as electron neutrinos make their way from the sun's core to the surface, they pass through a whole lot of matter and some fraction of them change from electron neutrinos to muon-neutrinos in the process. So, the first order of business was to try to detect muon-neutrinos coming from the sun.
The search for the muon-neutrino
In the 1980s the search for the muon-neutrino was underway. New detectors were built for this purpose. The new detectors used large tanks of water or heavy water lined with thousands of photomultiplier tubes to detect the tiny flash of light emitted when a neutrino struck an electron in the tank. The advantages of this technique were that it provided real-time detection of neutrinos, their energies and the direction from which they originated. It wasn't long before muon-neutrinos were detected, which provided strong support for the oscillation theory. However, more testing was needed to definitively show that neutrinos can change flavor in flight.
Particle accelerators save the day
Here is where the story gets a little scary...
So scientists conceived of a brilliant way to show that neutrinos change flavor in flight. If they could fire a beam of known neutrinos at one of the deeply buried detectors then they could compare what is detected to what was shot at the detector. In the mid-90s, the Fermi lab accelerator was used for this purpose. It produced a beam of muon-neutrinos that was aimed through the earth at a detector hundreds of miles away. Sure enough, by the time the muon-neutrinos reached the detector a large fraction of them had converted into electron-neutrinos. This pretty much sealed the deal for the oscillation theory.
Conclusion
The serious problem I see with all of this is that particle accelerators have routinely been shooting high energy neutrinos into the earth for many years now. The CERN accelerator fires a neutrino beam with an energy of 17 GeV right through the earth all the way to a detector in Italy ( [link to arxiv.org] Compare this to the maximum energy of neutrinos emitted by the sun - only 20 MeV ( [link to lappweb06.in2p3.fr] This means that CERN is bombarding the earth with neutrinos that are nearly 1000 times more energetic than what we receive from the sun! Moreover, these are muon-neutrinos. There is no known cosmic source of muon-neutrinos hitting the earth at such high energy.
Are you following me? The earth is being hit by the rare muon-neutrino at very high energy. Remember that the higher the energy, the more likely the neutrino is to interact with matter. What might be the effects on the earth? Could it be possible that this type/energy neutrino might influence the rate of radioactive decay of isotopes in the earth? There is already some evidence that neutrinos can have this kind of effect ( [link to news.stanford.edu]
Personally, I would find it very poetic (albeit frightening and disturbing) if such a subtle energy form unleashed by man were to destroy our earth. This unbelivably tiny and almost massless particle may end up being the ghost that haunts us all.
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