Neutron skin impurity from Coulomb core polarization in ${}^{208}\text{Pb}$: Insights from PREX-II and validation via the ${(}^3\text{He},t)$ isobaric analog state reaction

Abstract

I investigate the effect of Coulomb core-polarization in ${}^{208}\text{Pb}$, highlighting its impact on uncertainties in neutron distribution measurements due to the discrepancy between neutron excess and neutron skin regions at the surface. This effect is validated using the ${(}^3\text{He},t)$ isobaric analog state (IAS) reaction at 420 MeV. My findings reveal that the Coulomb boundary radius, where core-polarization becomes negligible, is critical for accurately probing the neutron skin region in the target nucleus. Consequently, I propose extending the ${}^{208}\text{Pb}{(}^3\text{He},t)$IAS reaction experiment conducted by Zegers et al. [Phys. Rev. Lett. 99, 202501 (2007)] to measure cross sections up to 3${}^{\circ }$ angles to more precisely determine the neutron skin thickness in ${}^{208}\text{Pb}$ from theoretical reaction analysis. Additionally, I observe that, under the assumption of a large neutron skin in ${}^{208}\text{Pb}$, as suggested by the PREX-II result, the core-polarization effect introduces impurity into the neutron skin region.

6 pages, 4 figures. Accepted for publication as a Letter in Physical Review C

References in corpus (5)

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• On the extraction of weak transition strengths via the (3He,t) reaction at 420 MeV