Science: Radium E

Since the Curie-Joliots of Paris discovered artificial radioactivity two years ago (TIME, Feb. 12, 1934), some 40 substances, including salt and copper, have been made radioactive by bombardment with atomic particles. But, unlike radium, these substances are not radioactive in nature. Last week another milestone in the galloping progress of atomic transmutation was marked by the disclosure of a few atoms of Radium E created in the laboratories of the University of California.

Radium E is the seventh and last stage of radium disintegration before it turns into polonium. Its atomic weight is 210. Atomic weight of bismuth is 209. Dr. John Jacob Livingood figured that if he hurled billions of particles of atomic weight i at bismuth, some of them might plow into the nucleus and stick, turning the bismuth into Radium E. Actually, the best particles for his purpose were deuterons whose atomic weight is 2. When the deuterons got close to the bismuth nucleus, they broke into protons and neutrons. The protons recoiled. But the neutrons, of atomic weight i, slipped in.

Dr. Livingood identified the created element by the fact that it began shooting out fast electrons which dwindled by half in about five days. This is exactly the behavior of Radium E.