Low energy elastic scattering of hydrogen, deuterium and tritium on helium isotopes

B. J. P. Jones; A. Negi; A. Semakin

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arXiv · 2601.22360

Low energy elastic scattering of hydrogen, deuterium and tritium on helium isotopes

B. J. P. Jones·A. Negi·A. Semakin

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Abstract

Motivated by the needs of atomic tritium sources for neutrino mass experiments and Doppler-free two-photon 1S-2S spectroscopy in atomic deuterium and tritium, we present calculations of energy-dependent elastic scattering cross sections of hydrogen isotopes (H, D and T) on helium isotopes ($^3$He and $^4$He) in the temperature range 1~mK to 300~K. The tritium-on-helium cross sections are found to be enhanced over their hydrogen-on-helium counterparts by a near-threshold resonant \textit{s}-wave bound state at low energy, similar to one that has been predicted in the triplet T-T system. While the energy-dependent cross sections span a wide range at low energy due to this \textit{s}-wave enhancement, they tend toward a common value at high energy where the scattering becomes effectively geometric in nature.

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B. J. P. Jones, A. Negi, A. Semakin. 2026-01-29. Low energy elastic scattering of hydrogen, deuterium and tritium on helium isotopes. https://arxiv.org/abs/2601.22360

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