Abstract
A method for measuring the average longitudinal polarization of the electron beam at an electron-positron collider operating near the J/ψ resonance is proposed. The method utilizes the differential cross-section of \( J/\psi \to \left[\Lambda \to p{\pi}^{-}\right]\left[\Lambda \to \overline{p}{\pi}^{+}\right] \) decay. It can be used to measure the average longitudinal polarization of electrons with the statistical precision better than 10−3 at a Super Charm-Tau factory operating at the luminosity of 1035 cm−2s−1. The method is discussed in the context of the weak mixing angle measurement in the same experiment.
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ArXiv ePrint: 1912.09760
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Open Access . This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.
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Bondar, A., Grabovsky, A., Reznichenko, A. et al. Measurement of the weak mixing angle at a Super Charm-Tau factory with data-driven monitoring of the average electron beam polarization. J. High Energ. Phys. 2020, 76 (2020). https://doi.org/10.1007/JHEP03(2020)076
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DOI: https://doi.org/10.1007/JHEP03(2020)076
Keywords
- e+-e- Experiments
- Electroweak interaction
- Polarization