A neutral η0 (having mass 0.642 u) that is at rest decays into two gamma ray photons. What is the energy in MeV of each photon? (1 u = 931.5 MeV/c²) A) 299 MeV B) 597 MeV C) 1190 MeV D) 199 MeV E) 149 MeV

Question

Quizplus · Accepted Answer

The energy of each photon is half the rest energy of the η0 particle. The rest energy is calculated as 0.642 u * 931.5 MeV/u = 597 MeV. Each photon has an energy of 597 MeV / 2 = 298.5 MeV, which rounds to 299 MeV.

A Neutral η0 (Having Mass 0