Monthly Colloquium

Special colloquium by Prof.Gottfried Munzenberg and Prof.Yuri Tsolakovich Oganessian

Nishina Hall

Nishina Hall

=Date and Time=
Mar.13th(Mon.) 15:00~ at Nishina Hall

=Title and Lecturer=
"Nihonium, Super heavy nuclei -some historical remarks-"
by Prof.Gottfried Munzenberg(GSI, University of Mainz)

=Title and Lecturer=
"Discovery of Super heavy Nuclei"
by Prof.Yuri Tsolakovich Oganessian(Flerov Laboratory of Nuclear Reactions JINR)

 The first experimental evidence of the existence of superheavy nuclei (SHN) were obtained in 2000 in complete  fusion reactions of the target nuclei 244Pu and 248Cm with 48Ca-projectiles. These results have opened up new possibilities of synthesis of the heaviest nuclei and study of nuclear / atomic properties of the superheavy elements.
As a result of the experiments performed with use of a beam of 48Ca ions and neutron-rich isotopes of actinides, the heaviest elements with atomic numbers 113-118 were synthesized. In these investigations 53 new nuclides, isotopes of elements 104-118 having the largest number of neutrons, were produced for the first time, and their decay properties have been determined.
A significant increase in the stability of the SHN with the number of neutrons, their relatively high cross sections caused high fission barriers; scenario and decay characteristics of new nuclides appeared a direct indication of the existence of a region like island of stability among very heavy (superheavy) elements, predicted more than 45 years ago.
In the talk the experimental approaches to the synthesis of SHN and brief compares experimental data with macro-microscopic theory are given.  Some prospects associated with the new accelerator and experimental facilities are discussed also.
The experiments where performed at FLNR of the Joint Institute for Nuclear Research (Dubna) in collaboration with Livermore National Laboratory (Livermore), Oak- Ridge National Laboratory (Knoxville) and Vanderbilt University (Nashville).