The challenging direct measurement of the 65 keV resonance strength of the 17O(p,γ)18F reaction at LUNA

Giovanni Francesco Ciani,For The Luna Collaboration ,Denise Piatti,Riccardo Maria Gesuè

doi:10.1051/epjconf/202226011003

Giovanni Francesco Ciani, For The Luna Collaboration + Show 2 more

Open Access

https://doi.org/10.1051/epjconf/202226011003

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Abstract

A precise determination of proton capture rates on oxygen is mandatory to predict the abundance ratios of the oxygen isotopes in a stellar environment where hydrogen burning is active. The 17O(p,γ)18F reaction, speciﬁcally, plays a crucial role in AGB nucleosynthesis as well as in explosive hydrogen burning occurring in type Ia novae. At temperatures of interest for the former scenario (20 MK ≤ T ≤ 80 MK) the main contribution to the astrophysical reaction rate comes from the Ec.m. = 65 keV resonance. The strength of this resonance is presently determined only through indirect measurements, with an adopted value of ωγ = (1.6 ± 0.3) × 10−11 eV. Thanks to the low background environment of the Laboratori Nazionali del Gran Sasso, the intense and stable beam provided by the LUNA 400 kV accelerator and the experience in oxygen target production, the LUNA collaboration is aiming the ﬁrst direct measurement of the above mentioned resonance strength. In the present work details of challenging direct measurement planned at LUNA will be described.

Highlights

A precise determination of proton capture rates on oxygen is mandatory to predict the abundance ratios of the oxygen isotopes in a stellar environment where hydrogen burning is active
The 17O(p,γ)18F reaction (Q = 5607.1(5)[1]) participates in the NO section of the CNO cycle, which is the main H-burning cycle in H-shell of giant stars or in explosive scenarios as type Ia novae.Oxygen isotopic ratios in H-burning shell of Red Giant Branch (RGB) and Asymptotic Giant Branch (AGB) stars only depend on the rate of proton capture reaction on oxygen
Thanks to the low background environment of the Laboratori Nazionali del Gran Sasso, the intense and stable beam provided by the Laboratory for Underground Nuclear Astrophysics (LUNA) 400 kV accelerator and the experience in oxygen target production, the LUNA collaboration is aiming the first direct measurement of the above mentioned resonance strength

Summary

Introduction

A precise determination of proton capture rates on oxygen is mandatory to predict the abundance ratios of the oxygen isotopes in a stellar environment where hydrogen burning is active. The strength of this resonance is presently determined only through indirect measurements, with an adopted value of ωγ = (1.6 ± 0.3) × 10−11 eV. Thanks to the low background environment of the Laboratori Nazionali del Gran Sasso, the intense and stable beam provided by the LUNA 400 kV accelerator and the experience in oxygen target production, the LUNA collaboration is aiming the first direct measurement of the above mentioned resonance strength.

Results

Conclusion