Questions of Elementary Particles
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3.13 A pion traveling at speed v decays into a muon and a neutrino, pi^- –> mu^- + v_mu. If the neutrino emerges at 90 degrees to the original pion direction, at what angle does the mu come off?
3.14 Particle A (energy E) hits particle B (at rest), producing particles C_1, C_2, … A + B –> C_1 + C_2 + … + C_n. Calculate the threshold (i.e., minimum E) for this reaction, in terms of the various particle masses.