A new Isotope of Z=105 with mass number 259

An Isotope of element 105 with mass number 259 has been produced via the re action Am-241(Ne-22,4n) (259)Db at E-lab = 120MeV. The reaction products we re transported and collected using the helium-jet technique and rotating wh eel apparatus. The alpha -decays of the products and their daughter nuclide s were detected by a series of Si(Au) detectors. The Z and A of the nuclide have been unambiguously identified by the genetic relationship between the new activity and the known nuclide Lr-255. The new nuclide (259)Db has a h alf-life of (0.51 +/- 0.16)s and decay by alpha-particle emission with ener gy of 9.47MeV. The Q(a) value for new isotope (259)Db is in good coincidenc e with the predicted result.