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arXiv · 2611.00613

Probing nuclear deformation through global $Λ$ polarization in U$+$U collisions at HIAF

Shin-ei Fujii·Kiochi Hattori
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Abstract

We investigate the effects of nuclear deformation on global $Λ$ polarization in U+U collisions at $\sqrt{s_{NN}}=2.85$~GeV using the JAM2 transport model, in view of future measurements at HIAF. The tip--tip and side--side configurations yield substantially larger global $Λ$ polarization than that in the body--body configuration. This separation grows with an increasing quadrupole deformation parameter $β_2$, highlighting the sensitivity of orientation-dependent polarization to nuclear deformation. These findings connect nuclear shape with hyperon spin, opening a new avenue for probing nuclear deformation through polarization measurements in intermediate-energy heavy-ion collisions.

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Shin-ei Fujii, Kiochi Hattori. 2026-10-31. Probing nuclear deformation through global $Λ$ polarization in U$+$U collisions at HIAF. https://arxiv.org/abs/2611.00613

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