640 Particle Physics and CosmologyP46.53The total energy in neutrinos emitted per second by the Sun is:04 4 15 1011 1011223...afejπ×LNMOQP=×W W.Over 109years, the Sun emits 36 1039.×J in neutrinos. This represents an annihilated massmc23936 10. Jm40 1022kg.About 1 part in 50 000 000 of the Sun’s mass, over 109years, has been lost to neutrinos.P46.54pp p+→+ ++XWe suppose the protons each have 70.4 MeV of kinetic energy. From conservation of momentum forthe collision, particle Xhas zero momentum and thus zero kinetic energy. Conservation of systemenergy then requiresMcM cMc KXppppp22 222++=+++Mc McK McX2222938 32 70 4139 6939 5=+−=+−=ppMeVMeVMeVMeV....afXmust be a neutral baryon of rest energy 939.5 MeV. Thus Xis a neutron .*P46.55(a)If 2Nparticles are annihilated, the energy released is 22Nmc. The resulting photonmomentum is pEcNmccNmc===222. Since the momentum of the system is conserved, the
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This note was uploaded on 12/15/2011 for the course PHY 203 taught by Professor Staff during the Fall '11 term at Indiana State University .