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DOE OSTI · 1660446

Weak charge and weak radius of 12 C

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

Here, 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 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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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Koshchii, Oleksandr, Erler, Jens, Gorchtein, Mikhail, Horowitz, Charles J., Piekarewicz, Jorge, Roca-Maza, Xavier, Seng, Chien-Yeah, Spiesberger, Hubert. 2020-08-11. Weak charge and weak radius of 12 C. https://doi.org/10.1103/physrevc.102.022501

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