Synthetic radioactive element number 102, aw 254, one of the actinide series of elements; its discovery has been claimed by research groups in Sweden, the former U.S.S.R., and California. It can be produced in a cyclotron by bombarding copper with nuclei of carbon-13 accelerated to high energies. The name nobelium has been accepted by the IUPAC Commission on Nomenclature of Inorganic Chemistry. It has nine isotopes (251–259) that are so short-lived that their chemical properties have not been determined. It has no known uses or compounds.