GSI experiments on the synthesis of superheavy elements

Journal Article · Sun Feb 15 00:00:00 EST 1998 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.55134· OSTI ID:21182558

Hessberger, F P; Hofmann, S; Ninov, V; Armbruster, P; Folger, H; Muenzenberg, G; Stodel, Ch ^[1]; Lavrentev, A; Popeko, A G; Yeremin, A N ^[2]; Leino, M E ^[3]; Saro, S ^[4]

---

1. Gesellschaft fuer Schwerionenforschung mbH, Planckstrasse 1, D-64291 Darmstadt (Germany)
2. Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna (Russian Federation)
3. University of Jyvaeskylae, Department of Physics, P.O. Box 35, FIN-40351 Jyvaeskylae (Finland)
4. Comenius University, Dept. of Nuclear Physics, Mlynska Dolina FJ, SK-84215 Bratislava (Slovakia)

Evaporation residue production was investigated at SHIP in cold fusion reactions of Pb- and Bi-target nuclei with projectiles of elements between Ti (Z=22) and Se (Z=34) leading to compound nuclei Z{sub CN}=104-116. The isotopes {sup 269}110, {sup 271}110, {sup 272}111, and {sup 277}112 of the elements Z=110, Z=111 and Z=112 were unambiguously identified for the first time in bombardments of {sup 208}Pb, {sup 209}Bi with {sup 62,64}Ni and {sup 70}Zn. Excitation functions for {sup 50}Ti+{sup 208}Pb and {sup 58}Fe+{sup 208}Pb were measured with high precision, three new spontaneous fission (sf) activities {sup 253}104, {sup 254}104, {sup 258}106 were identified. A small {alpha}-decay branch of the even-even nucleus {sup 256}104 (b{sub {alpha}}{approx_equal}0.003) was confirmed, allowing to estimate mass excesses {delta}mc{sup 2} for N-Z=48 nuclei up to {sup 264}Hs (Z=108). An analysis of the {alpha}-decay chains observed in a bombardment of {sup 209}Bi with {sup 58}Fe projectiles showed evidence for an isomeric state in {sup 266}Mt (Z=109). We further report on an attempt to produce element 116 and a second isotope of element 112 by the reactions {sup 82}Se+{sup 208}Pb and {sup 68}Zn+{sup 208}Pb, respectively.

• OSTI ID: 21182558
• Journal Information: AIP Conference Proceedings, Vol. 425, Issue 1; Conference: Tours symposium on nuclear physics III, Tours (France), 2-5 Sep 1997; Other Information: DOI: 10.1063/1.55134; (c) 1998 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA DECAY
BISMUTH 209 TARGET
ELEMENT 112
ELEMENT 116
EXCITATION FUNCTIONS
HASSIUM 264
HEAVY ION FUSION REACTIONS
IRON 58 REACTIONS
ISOMERIC NUCLEI
LEAD 208 TARGET
MEITNERIUM 266
NICKEL 62 REACTIONS
NICKEL 64 REACTIONS
SELENIUM 82 REACTIONS
SPONTANEOUS FISSION
TITANIUM 50 REACTIONS
ZINC 68 REACTIONS
ZINC 70 REACTIONS