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Q:
I'e been reading that a neutrino nhas no electirc charge. But what about an electron neutrino (one of the three flavours)? Wouldn't this have a negative charge?
- Marc Inberg
Sydney Australia
A:
No, all three flavors of neutrinos have zero charge. For example a neutron can decay into a proton, an electron, and an electron anti-neutrino. Since charge is conserved and the fact that the charge on the electron is exactly equal and opposite to that of the proton, that means there is nothing left over for the neutrino. The neutrinos have slightly different interaction properties that distinguish them but electric charge is not among them.
LeeH
(published on 05/02/2009)
Follow-Up #1: More about neutrinos
Q:
deacay into an electron anti-neutrino?
i am asking about an electron neutrino which travels through the human body and possibly alters velocity and direction of a moving human body through the neutrinos charge attraction to ion charges in cellular fluid causing deploarisations etc?
If thois hypothesis was true the electron neutrino would have to have a charge, wouldnt it?
- MArc
Australia
A:
Dear Marc,
First of all, don't worry about the 50 Trillion neutrinos from the sun that pass through your body every second. Their interactions with ordinary matter are so weak and infrequent that you might get one or two during your lifetime. If so, it would probably disrupt a single cell. No big deal. Scientists who study solar neutrinos build detectors weighing tons and are lucky to get a handful of events per month. Other naturally occurring radioactive materials in the earth's crust are far more likely to interact and are more harmful to cells.
Now about nomenclature. Neutrinos associated with electrons are called electron-neutrinos because they are always associated with interactions containing electrons. Muon-neutrinos are always associated with muons and tau-neutrinos with tau mesons. These two latter types refuse to interact with electrons. All three have zero charge. You were concerned about neutrinos interacting without having charge. Charge is not necessary for an interaction to happen. For example both neutrons and gamma rays have zero charge but interact happily with other particles: via the strong force and the first case and electromagnetic interactions in the second. Neutrinos interact via the so-called weak force. I recommend that you check out the web site:
http://en.wikipedia.org/wiki/Neutrino for more information.
LeeH
(published on 05/13/09)
Follow-up on this answer.
