1. Objective: additional identification of odd Z=113, 115 and 117 nuclei Radioactive properties of even-Z nuclei In accordance with the criteria for the discovery of elements previously established by the 1992 IUPAC/IUPAP Transfermium Working Group (TWG), and reinforced in subsequent IUPAC/IUPAP JWP discussions, it was determined that the Dubna-Livermore collaborations share in the fulfillment of those criteria both for elements Z = 114 and 116.

2. Production properties of even-Z nuclei: yield curve Cross bombardments

3. chemical identification: group 5 element 268 Db Cross bombardments 1. More decay chains 2. Excitation function 3. Cross bombardments

4. Gas-Filled Recoil Separator  = 1.8 m B  max = 3.1 Tm max gradient = 13 T/m

5. Target thickness mg/cm 2 E lab (MeV)E exc (MeV)Beam dose x 10 18 Number of chains 0.3724838.0-42.33.73 0.3724334.0-38.33.36 0.3724031.1-35.311.77 0.8424131.4-36.24.85+1

6. Radioactive properties of odd-Z nuclei

8. Production properties of odd-Z nuclei: yield curve

9. Radioactive properties of odd-Z nuclei

11. 266-270 Db SF/  Future experiments: excitation function identification of Z by X-rays of 268 Rf identification of Z by X-rays of 268 Rf

12. Summary: Discovery of elements 113 and 115 produced in 2003 was confirmed by observation of 21 new decay chains originating from 288 115, the product of the 3n-evaporation channel of the reaction 243 Am+ 48 Ca. Decay properties of all the six nuclei 288 115, 284 113, 280 Rg, 276 Mt, 272 Bh, and 268 Db synthesized in 2003 are in full agreement with those measured in the recent experiments. Excitation function of the reaction 243 Am+ 48 Ca was measured at three lower projectile energies. Experiments are to be continued. Discovery of element 117 was confirmed by registration of the decay chain of 289 115 which was produced for the first time in the reaction 249 Bk( 48 Ca,4n) as the descendant nucleus of 293 117. The isotope 289 115 was synthesized in two cross bombardments.

13. Yu.Ts. Oganessian, 1 F.Sh. Abdullin, 1 P.D. Bailey, 2 D.E. Benker, 2 M.E. Bennett, 3 S.N. Dmitriev, 1 J.G. Ezold, 2 J. H. Hamilton, 4 R.A. Henderson, 5 M.G. Itkis, 1 A.N. Mezentsev, 1 K.J. Moody, 5 S.L. Nelson, 5 A.N. Polyakov, 1 C.E. Porter, 2 A.V. Ramayya, 4 F.D. Riley, 2 J.B. Roberto, 2 M.A. Ryabinin, 6 K.P. Rykaczewski, 2 R.N. Sagaidak, 1 D.A. Shaughnessy, 5 I.V. Shirokovsky, 1 M.A. Stoyer, 5 V.G. Subbotin, 1 R. Sudowe, 3 A.M. Sukhov, 1 R. Taylor, 2 Yu.S. Tsyganov, 1 V.K. Utyonkov, 1 A.A. Voinov, 1 G.K. Vostokin, 1 and P.A. Wilk 5 1 Joint Institute for Nuclear Research, RU-141980 Dubna, Russian Federation 2 Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA 3 University of Nevada Las Vegas, Las Vegas, Nevada 89154, USA 4 Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA 5 Lawrence Livermore National Laboratory, Livermore, California 94551, USA 6 Research Institute of Atomic Reactors, RU-433510 Dimitrovgrad, Russian Federation

16. 261 Sg 