Descrizione del progetto
I processi di cattura dei neutroni potrebbero aiutare a decifrare la formazione degli elementi pesanti
Scoprire i processi cosmici responsabili della formazione degli elementi è l’obiettivo finale dell’astrofisica nucleare. Affrontando la grande sfida della comprensione della nucleosintesi degli elementi pesanti, il progetto gRESONANT, finanziato dal CER, intende chiarire l’impatto degli effetti di struttura nucleare trascurati sui processi di cattura dei neutroni. Esplorando le risonanze di decadimento gamma a bassa energia in nuclei ricchi di neutroni e superpesanti, gRESONANT potrebbe migliorare la comprensione dei tassi di cattura dei neutroni astrofisici. Le attività proposte daranno il via a una nuova direzione di ricerca, dal momento che non esistono dati sulla risonanza gamma a bassa energia nei nuclei ricchi di neutroni e superpesanti. gRESONANT consentirà di stimare con maggiore precisione le sezioni d’urto sconosciute di cattura dei neutroni, portando a significativi progressi nell’astrofisica nucleare.
Obiettivo
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.
Campo scientifico
- natural sciencesphysical sciencestheoretical physicsparticle physicsparticle accelerator
- natural sciencesphysical sciencesastronomystellar astronomyneutron stars
- natural sciencesphysical sciencesastronomyphysical cosmologybig bang
- natural sciencesphysical sciencesastronomyastrophysics
- natural sciencesphysical sciencesastronomystellar astronomysupernova
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-STG - Starting GrantIstituzione ospitante
0313 Oslo
Norvegia