CLUSTER RADIOACTIVITIES

The spontaneous emission of 14-C, 20-O, 23-F, (22,24-26)-Ne, (28, 30)-Mg
and (32-34)-Si from parent nuclei with Z = 87-96 have been experimentally
observed since 1984 in Oxford, Orsay, Moskow, Berkeley, Geneva, Dubna,
Argonne, Vienna , Milano,  Livermore, Beijing confirming earlier predictions within a
german-romanian cooperation.

The most frequently cited paper, considered to be the starting point, is: NEW TYPE OF DECAY OF HEAVY NUCLEI
INTERMEDIATE BETWEEN FISSION AND ALPHA-DECAY, by A. Sandulescu, D. N. Poenaru and W. Greiner,
Soviet Journal Particles and Nuclei 11 (1980) 528-541.


Other contributors to this field from IFIN-HH, Department of Heavy Ion Physics and Department of Theoretical Physics, as well as from The Institut fuer Theoretische Physik der Johann-Wolfgang Goethe Universitaet, Frankfurt am Main are either co-authors of the papers listed below, or can be found
at the following web sites:

http://tandem.nipne.ro
http://www.theory.nipne.ro
http://fias.uni-frankfurt.de


This phenomenon has received a wide popularity. The event has been described not only by scientific journals (including "La Recherche" n. 159, 1984; "Science et Vie" n. 808, 1985 ; "Physics Bulletin" n.489, 1985, "Scientific American" n. 3, 1990 (translated into 9 languages), Europhysics News n. 5, 1996) but also by several newspapers in F. R. Germany, Hungary, Romania, etc.
There are more than 30 Popularization articles of this kind.

The Main Scientifical Achievements of our Group (see also the list of publications beginning with 1980)

Few illustrative examples are given below.

Figure 1: Prediction of 14-C radioactivity of 222- and 224-Ra, and Unified approach of alpha-decay, cluster radioactivities, and cold fission of 234-U.

Figure 2: Potential Energy Surfaces of 106-Te showing for the first time  the alpha valley with the detailed landscape around the saddle-point along the alpha valley.

Figure 3: Nuclear Chart of Cluster Emitters including very long half-lives (Tc) and small branching-ratios (b) relative to alpha-decay

Figure 4: Nuclear Chart of Cluster Emitters selcted to posses measurable half-lives and branching-ratios relative to alpha-decay

Figure 5: Experimentally Confirmed Cluster Emitters

Figure 6: Comparison of Experimentally Confirmed Half-lives with Predictions within Analytical Superasymmetric Fission Model (ASAF) The measured halflives, ranging from 10 to the power 11 to 10 to the power 26 sec, are  in good quantitative agreement with the predicted halflives and branching ratios.

Figure 7: Universal Curves compared with Geiger-Nuttal Plots

Figure 8: The Most Cited Publications

Figure 9: The Nuclear Chart of Experimentally Observed Alpha Emitters and of the 252-Cf fission fragments