Thick-target Yield of 65Cu(α,n)68Ga Near Threshold and Implications for Nuclear Medicine, Deep Underground Detector Backgrounds, and Nucleosynthesis
Abstract
We report thick target yields of 65Cu(α,n)68Ga from α energies Eα=6.5--8~MeV measured via neutron-counting at the Edwards Accelerator Laboratory at Ohio University. Our results agree with prior results based on single-foil irradiations, while disagreeing with thick-target yields inferred from stacked-foil irradiations by up to an order of magnitude. Based on comparisons of our and prior measurements to Hauser-Feshbach calculations, we estimate the thick-target yield for 68Ga from Eα=14~MeV impinging on 100\%-enriched copper (65Cu) is 161+5−24~MBq/μAh (for He++), which is in agreement with the current IAEA estimate of 156~MBq/μAh. At Eα=8~MeV, where radioimpurity-free production of 68Ga could be realized with a natural copper target, our yield estimate is nearly 4× lower than the IAEA estimate. We find that the 65Cu(α,n) cross section estimates presently employed for neutrino and dark matter detector backgrounds and the 65Cu(α,n) astrophysical reaction rate recently recommended for nucleosynthesis calculations are in agreement with our measurement results.
Versions
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BibTeX
@misc{meisel2026thicktarget,
title = {{Thick-target Yield of $^65$Cu($α,n)^68$Ga Near Threshold and Implications for Nuclear Medicine, Deep Underground Detector Backgrounds, and Nucleosynthesis}},
author = {Zach Meisel and Gula Hamad and Kristyn Brandenburg and Carl R. Brune and Don E. Carter and Joseph Derkin and Yenuel Jones-Alberty and Tom N. Massey and Doug Soltesz and Shiv K. Subedi and Alexander V. Voinov},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.01719},
eprint = {2610.01719},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.01719},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Thick-target Yield of ^65Cu(α,n)^68Ga Near Threshold and Implications for Nuclear Medicine, Deep Underground Detector Backgrounds, and Nucleosynthesis
AU - Zach Meisel
AU - Gula Hamad
AU - Kristyn Brandenburg
AU - Carl R. Brune
AU - Don E. Carter
AU - Joseph Derkin
AU - Yenuel Jones-Alberty
AU - Tom N. Massey
AU - Doug Soltesz
AU - Shiv K. Subedi
AU - Alexander V. Voinov
PY - 2026
DA - 2026/10/01
PB - arXiv
DO - 10.48550/arxiv.2610.01719
UR - https://arxiv.org/abs/2610.01719
AB - We report thick target yields of ^65Cu(α,n)^68Ga from α energies E_α=6.5--8~MeV measured via neutron-counting at the Edwards Accelerator Laboratory at Ohio University. Our results agree with prior results based on single-foil irradiations, while disagreeing with thick-target yields inferred from stacked-foil irradiations by up to an order of magnitude. Based on comparisons of our and prior measurements to Hauser-Feshbach calculations, we estimate the thick-target yield for ^68Ga from E_α=14~MeV impinging on 100\%-enriched copper (^65Cu) is 161^+5_−24~MBq/μAh (for He^++), which is in agreement with the current IAEA estimate of 156~MBq/μAh. At E_α=8~MeV, where radioimpurity-free production of ^68Ga could be realized with a natural copper target, our yield estimate is nearly 4× lower than the IAEA estimate. We find that the ^65Cu(α,n) cross section estimates presently employed for neutrino and dark matter detector backgrounds and the ^65Cu(α,n) astrophysical reaction rate recently recommended for nucleosynthesis calculations are in agreement with our measurement results.
ER -