What American physicist discovered the positron which explained Chinese physicist Chung-Yao Chao's earlier experiments with gamma rays?
Chung-Yao Chao:  When the positron was discovered by Carl David Anderson in 1932, confirming the existence of Paul Dirac's "antimatter", it became clear that positrons could explain Chung-Yao Chao's earlier experiments, with the gamma rays being emitted from electron-positron annihilation.
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