Nuclear Structure

Rules of Atomic Decay:

• conservation of charge: C (-1,0,+1)
• conservation of baryon number: BN (-1,0,+1)
• conservation of lepton number: LN (-1,0,+1)

baryons = heavy particles made of quarks (protons, neutrons)

• proton = uud; neutron = udd
• there are six quarks: top,down,bottom,up,strange,charmed

leptons are not made of quarks (electrons, neutrinos)

In order to satisfy the above rules a free neutron must decay as follows:
neutron ----> proton + electron + anti-neutrino
(half-life ~ 15 minutes)

• neutron: C = 0; BN = +1; LN = 0
• proton: C = +1; BN = +1; LN = 0
• electron C = -1; BN = 0; LN = +1
• anti-neutrino: C = 0: BN = 0; LN = -1
• Total Sums: C = 0; BN =+1; LN = 0

This is called beta decay so its really decay by emitting an electron

Some Animations:

• Fission Process
• The S(low) Process
• The R(apid) Process

Two Kinds of Uranium on Earth:

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