Speaker
Description
Neutron capture reactions are fundamental to understanding the synthesis of elements heavier than iron in stellar environments, occurring through the slow (s), intermediate (i), and rapid (r) neutron‑capture processes. While neutron‑capture cross sections along the valley of stability—particularly for stable or long‑lived isotopes—have been extensively studied, direct measurements on short‑lived nuclides (T₁/₂ ≪ 1 year) remain inaccessible with current techniques.
Heavy‑ion storage rings coupled to radioactive‑beam facilities provide a powerful platform for advancing such studies. Over the past decade, the ESR and CRYRING at GSI Darmstadt have enabled inverse‑kinematics measurements of astrophysically relevant reaction rates, though to date only for charged‑particle reactions. With the NRING project at CRYRING [1], we propose the first facility capable of performing direct neutron‑capture measurements on shorter-lived isotopes.
In this contribution, I will outline the NRING concept and discuss its expected capabilities and limitations. Ultimately, fully harnessing this new approach will require the development of a dedicated future “neutron‑capture storage ring” integrated with an ISOL facility—an advancement that could enable hundreds of direct neutron‑capture measurements on short‑lived nuclei down to half-lives of seconds in the coming decade. One possibility for such a new dedicated facility could be the TRIUMF Storage Ring (TRISR) [2] at the TRIUMF-ISAC facility.
[1] Ariel Tarifeño-Saldivia, César Domingo-Pardo, Iris Dillmann, Yuri A. Litvinov, "Direct Neutron Reactions in Storage Rings Utilizing a Supercompact Cyclotron Neutron Target", [https://arxiv.org/abs/2508.15465], subm. to Phys. Rev. Acc.and Beams (2026)
[2] I. Dillmann, O. Kester, et al., Eur. Phys. J. A59 (2023) 105.