Nuclear physics for stellar explosions

• Applicant: Professor Dr. Andreas Zilges
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2016 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 286691198

• Final Report Year: 2024

Final Report Abstract

The synthesis of the elements in our universe takes place in all stages of stellar evolution, from hydrogen burning in main sequence stars over subsequent burning phases to their eventual death, and even beyond, when stellar remnants collide or accrete mass from companion stars. The interplay between the astrophysical environments necessary to allow for nucleosynthesis and the nuclear reactions that facilitate the transmutation of one element into another gives rise to an abundance of nucleosynthesis processes the modelling of which requires information on a highly varied set of nuclear properties. With a focus on the production of the proton rich p-nuclei, thought to be produced mainly in stellar explosions classified as type II supernovae, this work program aimed at reducing uncertainties associated with the nucleus+α optical model potential (α-OMP), nuclear level densities (NLD) at high excitation energies, and the γ-strength function (γ-SF). These properties are used to calculate cross sections in the framework of Hauser-Feshbach statistical model calculations in order to model the vast reaction networks involved in the production of p-nuclei, particularly via the γ process. To study these properties, experimentally determined cross sections are compared to theoretical calculations.

Publications

• Constraining nuclear properties in 94Mo via a 93Nb(p,γ)94Mo total cross section measurement. Physical Review C, 101(3).
  Heim, F.; Scholz, P.; Mayer, J.; Müller, M. & Zilges, A.
  
• Insights into the statistical γ-decay behavior of 108Cd via radiative proton capture. Physical Review C, 101(3).
  Heim, F.; Scholz, P.; Körschgen, M.; Mayer, J.; Müller, M. & Zilges, A.
  
• Absolute 96Mo(p,n)96m+gTc cross sections and a new branching for the 96mTc decay. Physical Review C, 103(5).
  Heim, F.; Müller, M.; Wilden, S. & Zilges, A.
  
• Investigating the 109 Ag(p, γ)110Cd reaction and its underlying nuclear physics. Physical Review C, 103(5).
  Heim, F.; Mayer, J.; Müller, M.; Scholz, P. & Zilges, A.
  
• Determination of 170,172 Yb(α,n)173,175Hf reaction cross sections in a stacked-target experiment. Physical Review C, 107(3).
  Müller, M.; Heim, F.; Wang, Y.; Wilden, S. & Zilges, A.
  
• Results of total cross-section measurements of the 87Rb(p,γ)88Sr reaction. EPJ Web of Conferences, 279(2023), 11004.
  Wilden, Svenja; Heim, Felix; Müller, Martin & Zilges, Andreas