All Problems

Elementary Particles

Problem 6.299

A negative pion with kinetic energy \(T=50 \mathrm{MeV}\) disintegrated during its flight into a muon and a neutrino. Find the energy of the neutrino outgoing at right angles to the pion's motion direction.

Reveal Answer
Ev=1/2(mπ2mμ2)/(mπ+T)=22MeVE_{\mathbf{v}}=1 / 2\left(m_{\pi}^{2}-m_{\mu}^{2}\right) /\left(m_{\pi}+T\right)=22 \mathrm{MeV}