Resonant Nuclear Gamma Decay and the Heavy-Element Nucleosynthesis

Objective

THE GRAND CHALLENGE: The “Holy Grail” of nuclear astrophysics is to understand the astrophysical processes responsible for the formation of the elements. A particularly challenging part is the description of the heavy-element nucleosynthesis. The only way to build the majority of these heavy nuclides is via neutron-capture processes. Unaccounted-for nuclear structure effects may drastically change these rates.
MAIN HYPOTHESIS: Nuclear low-energy gamma-decay resonances at high excitation energies will enhance the astrophysical neutron-capture reaction rates.
NOVEL APPROACH: This proposal is, for the first time, addressing the M1 scissors resonance in deformed, neutron-rich nuclei and superheavy elements. A new experimental technique will be developed to determine the electromagnetic nature of the unexpected upbend enhancement. Further, s-process branch points for the Re-Os cosmochronology will be studied for the first time with the Oslo method.
OBJECTIVES:
1) Measure s-process branch point nuclei with the Oslo method
2) Radioactive-beam experiments for neutron-rich nuclei searching for the low-energy upbend and the M1 scissors resonance
3) Develop new experimental technique to identify the upbend’s electromagnetic nature
4) Superheavy-element experiments looking for the M1 scissors resonance
POTENTIAL IMPACT IN THE RESEARCH FIELD: This proposal will trigger a new direction of research, as there are no data on the low-energy gamma resonances neither on neutron-rich nor superheavy nuclei. Their presence may have profound implications for the astrophysical neutron-capture rates. Developing a new experimental technique to determine the electromagnetic character of the upbend is crucial to distinguish between two competing explanations of this phenomenon. Unknown neutron-capture cross sections will be estimated with a much better precision than prior to this project, and lead to a major leap forward in the field of nuclear astrophysics.

Fields of science

Host institution

UNIVERSITETET I OSLO

Net EU contribution

€ 1 443 472,00

Address

Problemveien 5-7
0313 Oslo
Norway

Region

Norge Oslo og Viken Oslo

Activity type

Higher or Secondary Education Establishments

Links

Contact the organisation Website

Participation in EU R&I programmes

HORIZON collaboration network

Other funding

€ 0,00

Beneficiaries (1)