Find the error in the following solution." The lepton has mass

PHYSICS · Subjective · Fermi University Physics · Particle Physics & Quantum Fields · Non-abelian gauge theory and QCD · Electroweak theory and the Standard Model

Particle Physics, Ch The Standard Model as a table you can predict from

Problem

Find the error in the following solution." The τ−\tau^- lepton has mass 1776.9 MeV/c21776.9\,\mathrm{MeV}/c^2, comfortably above the combined mass of a π−\pi^- (139.6 MeV/c2139.6\,\mathrm{MeV}/c^2) and a π0\pi^0 (135.0 MeV/c2135.0\,\mathrm{MeV}/c^2) plus a ντ\nu_\tau (mass negligible on this scale), so the channel τ−→π−π0ντ\tau^-\to\pi^-\pi^0\nu_\tau is open. Since the final state contains two pions, and pions are hadrons that interact through the strong force, this decay must go through a strong vertex. It is therefore a strong decay, and by the usual strong-interaction band its lifetime should be of order 10−23 s10^{-23}\,\mathrm{s}."

Browse the problem library