Energy Distribution ofγRays fromπ0Decay

It is shown that the $\gamma$-ray energy distribution resulting from the decay of ${\pi }^0$ mesons produced in a target bombarded by a high-energy particle beam is related in a simple manner to the differential ${\pi }^0$ production cross section, for sufficiently high energies of the $\gamma \text{'}\mathrm{s}$ (≳500 Mev). An expression is obtained for the ${\pi }^0$ production cross section in terms of the $\gamma$-ray energy distribution. This result is extended to the case of an arbitrary two-body decay, for which an expression is obtained for the production cross section of the primaries in terms of the energy distribution of the secondaries emitted in the decay.