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arXiv · 2005.00479

Weak charge and weak radius of ${}^{12}$C

Oleksandr Koshchii·Jens Erler·Mikhail Gorchtein·Charles J. Horowitz·Jorge Piekarewicz·Xavier Roca-Maza·Chien-Yeah Seng·Hubert Spiesberger
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Abstract

We present a feasibility study of a simultaneous sub-percent extraction of the weak charge and the weak radius of the ${}^{12}$C nucleus using parity-violating electron scattering, based on a largely model-independent assessment of the uncertainties. The corresponding measurement is considered to be carried out at the future MESA facility in Mainz with $E_{\rm beam} = 155$ MeV. We find that a combination of a $0.3\%$ precise measurement of the parity-violating asymmetry at forward angles with a $10\%$ measurement at backward angles will allow to determine the weak charge and the weak radius of ${}^{12}$C with $0.4\%$ and $0.5\%$ precision, respectively. These values could be improved to $0.3\%$ and $0.2\%$ for a $3\%$ backward measurement. This experimental program will have impact on precision low-energy tests in the electroweak sector and nuclear structure.

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Oleksandr Koshchii, Jens Erler, Mikhail Gorchtein, Charles J. Horowitz, Jorge Piekarewicz, Xavier Roca-Maza, Chien-Yeah Seng, Hubert Spiesberger. 2020-08-12. Weak charge and weak radius of ${}^{12}$C. https://doi.org/10.1103/physrevc.102.022501

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