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Neutron decay?

  1. Feb 17, 2007 #1
    I was just reading this..
    Free Neutron decays into proton, electron and neutrino.

    neutron --> proton + electron + v (neutrino)
    My Question:
    Neutron is chargeless. How can it give proton and neutron which are charged ?

    (If the question is simple i am sorry, I am new to nuclear physics)
  2. jcsd
  3. Feb 17, 2007 #2


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  4. Feb 17, 2007 #3
    Thats not my point..
    Can a neutral particle generate charged particle?

    That is what happened there..
  5. Feb 17, 2007 #4
    This is possible because the net charge of the entire system is still zero. Charge is conserved, so it all works out. I guess that naively, one could think of the neutron as a proton and an electron put together (which would be why neutron has no net charge). If that helps, anyway...
  6. Feb 17, 2007 #5
    I get it, Thanks.
  7. Mar 7, 2007 #6


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    A neutron is composed of 2 down quarks and 1 up quark. An up quark has a charge of +2/3, while down quarks have a charge of -1/3. In beta decay, a down quark turns into an up quark and emits an electron and a neutrino.
  8. Mar 16, 2007 #7
    Don't forget the virtual W- boson here...

    d --> u + W-
    W- --> e- + nubar

    so that;

    n --> p + e- + nubar

    (sorry I don't use LaTeX that often) Note that both baryon number and lepton number are conserved here. That is very important...
  9. Apr 6, 2007 #8
    neutron contains 3 quarks with the charges of 2/3+, 1/3-,1/3- so a -1/3 dcays into a +2/3 releasing a weak carrier particle which in turn decays into electron anti neutrino and a electron.

    Edit:Just saw the post above me.But also matter (particle with odd-half spin is conserved.
    HOW? Here:
    Say fermions were +1 and bosons were 0 and antifermions were -1
    the decay would look like this
    +1(neutron) -> (proton) +1 and +1 (electron) and -1(antineutrino)
    so 1 = 2- -1= 1
    hope you understand
  10. Nov 14, 2010 #9
    if two substances have the same amount of charge, but one positive and one negative, then it has a neutral charge :)
  11. Nov 14, 2010 #10

    Vanadium 50

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    This thread is 3 years old.
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