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arXiv · 2501.10550

Measurement of the mean excitation energy of liquid argon

M. Strait
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Abstract

The mean excitation energy (I-value) of liquid argon is a critical input for energy estimation in neutrino oscillation experiments. It is measured to be $(188\pm8)$eV using the range of 404MeV protons from the Fermilab Linac. This compares to the author's recent evaluation of $(197\pm7)$eV based on a combination of an oscillator strength distribution analysis, gaseous argon range measurements, sparse stopping power data on solid argon, and an extrapolation of data on the effect of phase from other substances. Using all sources of information, we recommend a value of $(193\pm5)$eV for liquid argon.

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M. Strait. 2025-01-17. Measurement of the mean excitation energy of liquid argon. https://arxiv.org/abs/2501.10550

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