Searching the Stabilizing Effects of Neutron Shell Closure via Fusion Evaporation Residue Studies

Searching the “Island of stability” is a topic of
extreme interest in theoretical as well as experimental modern
physics today. This “island of stability” is spanned by superheavy
elements (SHE's) that are produced in the laboratory. SHE's are
believed to exist primarily due to the “magic” stabilizing effects of
nuclear shell structure. SHE synthesis is extremely difficult due to
their very low production cross section, often of the order of pico
barns or less. Stabilizing effects of shell closures at proton number
Z=82 and neutron number N=126 are predicted theoretically. Though
stabilizing effects of Z=82 have been experimentally verified, no
concluding observations have been made with N=126, so far. We
measured and analyzed the total evaporation residue (ER) cross
sections for a number of systems with neutron number around 126 to
explore possible shell closure effects in ER cross sections, in this
work.

Authors:

• B. R. S. Babu
• E. Prasad
• P. V. Laveen
• A. M. Vinodkumar

Keywords:

• Superheavy element
• fusion evaporation
• evaporation reside
• compound nucleus.

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