Problem 1: A pion 7- traveling at speed v decays into a muon u- and an antineutrino (T- → u- +ū,). To a good approximation, we can assume the antineutrino is massless. On the other hand, the pion and muon have masses m, and m, respectively. If the antineutrino emerges at 90° to the original pion direction, show that the angle 0 at which the muon comes off is given by 1– m², /m² 23y2 tan where B = v/c and y = 1//1 – 32.

Problem 1: A pion 7- traveling at speed v decays into a muon u- and an antineutrino (T- → u- +ū,). To a good approximation, we can assume the antineutrino is massless. On the other hand, the pion and muon have masses m, and m, respectively. If the antineutrino emerges at 90° to the original pion direction, show that the angle 0 at which the muon comes off is given by 1– m², /m² 23y2 tan where B = v/c and y = 1//1 – 32.