Accurate measurement of the electron beam polarization in JLab Hall A using Compton polarimetry

S. Escoffier; P. Y. Bertin; M. Brossard; E. Burtin; C. Cavata; N. Colombel; C. W. de Jager; A. Delbart; D. Lhuillier; F. Marie; J. Mitchell; D. Neyret; T. Pussieux

doi:10.1016/j.nima.2005.05.067

arXiv · physics/0504195

Accurate measurement of the electron beam polarization in JLab Hall A using Compton polarimetry

S. Escoffier·P. Y. Bertin·M. Brossard·E. Burtin·C. Cavata·N. Colombel·C. W. de Jager·A. Delbart·D. Lhuillier·F. Marie·J. Mitchell·D. Neyret·T. Pussieux

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Abstract

A major advance in accurate electron beam polarization measurement has been achieved at Jlab Hall A with a Compton polarimeter based on a Fabry-Perot cavity photon beam amplifier. At an electron energy of 4.6 GeV and a beam current of 40 uA, a total relative uncertainty of 1.5% is typically achieved within 40 min of data taking. Under the same conditions monitoring of the polarization is accurate at a level of 1%. These unprecedented results make Compton polarimetry an essential tool for modern parity-violation experiments, which require very accurate electron beam polarization measurements.

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S. Escoffier, P. Y. Bertin, M. Brossard, E. Burtin, C. Cavata, N. Colombel, C. W. de Jager, A. Delbart, D. Lhuillier, F. Marie, J. Mitchell, D. Neyret, T. Pussieux. 2005-04-27. Accurate measurement of the electron beam polarization in JLab Hall A using Compton polarimetry. https://doi.org/10.1016/j.nima.2005.05.067

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