A high-energy physicist at CERN observes that a certain particle decays into two secondary particles, which then each decay into two photons. If the initial particle has a mass of 128 GeV/c² and the two secondary particles each carry equal energy, what is the total energy of all the resulting photons?

Thu, 30 Apr 2026 02:30:10 +0000

CERN Physicist Reveals Energy Distribution in a Decay Chain: From Massive Particle to Photons In a groundbreaking observation at CERN, a leading high-energy physicist has analyzed the decay of a massive particle with a mass of 128 GeV/c², shedding light on how energy is distributed across a cascade of secondary particles. The particle decays into two identical secondary particles, which in turn each decay into two photons. This detailed insight highlights the conservation of energy in fundamental particle interactions—an essential principle in quantum field theory. According to the analysis, the initial particle’s rest mass energy is 128 GeV, as per Einstein’s famous equation E = mc², where c (the speed of light) is normalized in natural units (GeV/c²). This total energy is conserved throughout the decay chain. The primary particle decays into two secondary particles of equal energy, meaning each carries half the mass-energy of the parent:
Energy of each secondary particle = 128 GeV / 2 = 64 GeV. In the next stage, each secondary particle decays into two photons. Since energy is additive and conserved, each photon receives exactly 64 GeV of energy. Thus, from two photons, the total energy output from this secondary decay step is:
2 photons × 64 GeV = 128 GeV.