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arXiv · 1109.5771

The beam energy measurement system for the Beijing electron-positron collider

E. V. Abakumova·M. N. Achasov·V. E. Blinov·X. Cai·H. Y. Dong·C. D. Fu·F. A. Harris·V. V. Kaminsky·A. A. Krasnov·Q. Liu·X. H. Mo·N. Yu. Muchnoi·I. B. Nikolaev·Q. Qin·H. M. Qu·S. L. Olsen·E. E. Pyata·A. G. Shamov·C. P. Shen·K. Yu. Todyshev·G. S. Varner·Y. F. Wang·Q. Xiao·J. Q. Xu·J. Y. Zhang·T. B. Zhang·Y. H. Zhang·A. A. Zhukov
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Abstract

The beam energy measurement system (BEMS) for the upgraded Beijing electron-positron collider BEPC-II is described. The system is based on measuring the energies of Compton back-scattered photons. The relative systematic uncertainty of the electron and positron beam energy determination is estimated as 2 \cdot 10^{-5}. The relative uncertainty of the beam's energy spread is about 6 %.

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E. V. Abakumova, M. N. Achasov, V. E. Blinov, X. Cai, H. Y. Dong, C. D. Fu, F. A. Harris, V. V. Kaminsky, A. A. Krasnov, Q. Liu, X. H. Mo, N. Yu. Muchnoi, I. B. Nikolaev, Q. Qin, H. M. Qu, S. L. Olsen, E. E. Pyata, A. G. Shamov, C. P. Shen, K. Yu. Todyshev, G. S. Varner, Y. F. Wang, Q. Xiao, J. Q. Xu, J. Y. Zhang, T. B. Zhang, Y. H. Zhang, A. A. Zhukov. 2011-09-27. The beam energy measurement system for the Beijing electron-positron collider. https://doi.org/10.1016/j.nima.2011.08.050

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