Lightest isotope of Bh produced via the 209Bi(52Cr,n)260Bh reaction

NUCL 11

Sarah L. Nelson, slnelson@lbl.gov1, Kenneth E. Gregorich, kegregorich@lbl.gov2, Irena Dragojevic3, Mitch A. Garcia4, Jacklyn M. Gates, jmgates@lbl.gov5, Ralf Sudowe, ralf.sudowe@unlv.edu2, and Heino Nitsche, hnitsche@lbl.gov6. (1) Nuclear Science Division, Lawrence Berkeley National Laboratory and Department of Chemistry, UC Berkeley, 1 Cyclotron Rd., MS88R0192, Berkeley, CA 94720, (2) Nuclear Science Division, Lawrence Berkeley National Laboratory, MS 88R0192, 1 Cyclotron Rd., Berkeley, CA 94720-8101, (3) Nuclear Science Division, LBNL and Department of Chemistry, UC Berkeley, 1 Cyclotron Road, MS 88R0192, Berkeley, CA 94720, (4) College of Chemistry, UC Berkeley, 446 Latimer, Berkeley, CA 94720, (5) Nuclear Science Division, Lawrence Berkeley National Lab/UC Berkeley Department of Chemistry, 1 Cyclotron Rd., MS70R0319, Berkeley, CA 94720, (6) Nuclear Science Division, University of California, Berkeley, Department of Chemistry and Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 70R0319, Berkeley, CA 94720
The lightest isotope of Bh known was produced in the new 209Bi(52Cr,n)260Bh reaction at the Lawrence Berkeley National Laboratory 88 Inch Cyclotron. Positive identification was made by observation of eight correlated alpha particle decay chains in the focal plane detector of the Berkeley Gas-Filled Separator. 260Bh decays with a 35 +19-9 ms half-life by alpha particle emission mainly by a group at 10.16 MeV. The measured cross section of 59 +29-20 pb is compared to “Fusion by Diffusion” model predictions proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski. [1,2] The influence of the N = 152 and Z = 108 shells on alpha decay properties will be discussed.

[1] W. J. Swiatecki, K. Siwek-Wilczynska, and J. Wilczynski, Acta Physica Polonica B 34, 2049 (2003).

[2] W. J. Swiatecki, K. Siwek-Wilczynska, and J. Wilczynski, Physical Review C 71, 014602 (2005).

Acknowledgements:

This work was supported by the Director, Office of Science, Nuclear Physics, U.S. Department of Energy under contract number DE-AC02-05CH11231.

 

Developments in Advanced Characterization Techniques in Actinide and Transactinide Science
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