Shortly after the discovery of neutrons by Chadwick in 1932, the Soviet physicist Landau proposed that a class of stars could all be composed of neutrons, making Landau the first scholar to propose the concept of neutron stars. In 1934, Bud and Zweiki published an article in Physical Review, believing that supernova explosion can transform an ordinary star into a neutron star, and pointing out that this process can accelerate particles and produce cosmic rays. Oppenheimer and Volkow establish...