18–22 May 2026
Helga Engs Hus
Europe/Oslo timezone

Constraining the $^{95}$Zr(n,$\gamma$) cross section using SONIC at Horus

19 May 2026, 10:40
20m
Auditorium 1 (Helga Engs Hus)

Auditorium 1

Helga Engs Hus

Sem Sælands vei 7, 0371 OSLO Norway

Speaker

Dennis Muecher (Institute for Nuclear Physics, University of Cologne)

Description

The $^{95}$Zr(n,$\gamma$) cross section is crucial for understanding the intermediate neutron capture process (i process), as it directly affects the production and abundance of Molybdenum isotopes. The observed Molybdenum overabundance in presolar grains represents one of the most significant signatures of i-process nucleosynthesis. At the same time, $^{95}$Zr remains a branching point in the slow neutron capture process (s process), where its long-lived nature allows β-decay to compete with the formation of $^{96}$Zr.
Because $^{95}$Zr is unstable, a direct measurement of its neutron capture cross section is currently not feasible. Using the Oslo method, we have experimentally constrained the $^{95}$Zr(n,γ) cross section for the first time. The $^{96}$Zr(p,p’) reaction was studied at the 10 MV FN-Tandem accelerator at the Institute for Nuclear Physics, University of Cologne, employing the SONIC@HORUS detector array. By applying the newly developed “Shape” method, we significantly reduced model uncertainties. We present preliminary results and discuss their implications for i-process nucleosynthesis, with reference to the s process.

Author

Dennis Muecher (Institute for Nuclear Physics, University of Cologne)

Presentation materials