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arXiv · hep-ex/0201033

Electron polarization measurement using a Fabry-Perot cavity at HERA

Zhiqing Zhang
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Abstract

A new Compton longitudinal polarimeter currently under construction for HERA is presented. The key component of the polarimeter is a Fabry-Perot cavity located around the electron beam pipe. With such an optical cavity, a continuous laser power equivalent to 5 kW, much higher than those commercially available, can be achieved, leading to one backscattered photon per bunch crossing. This ``few-photon mode'' will allow a very precise determination of the calorimeter response with little systematic uncertainty. The electron polarization measurement at the per mill level is expected.

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Zhiqing Zhang. 2002-01-21. Electron polarization measurement using a Fabry-Perot cavity at HERA. https://arxiv.org/abs/hep-ex/0201033

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