Calibration of the Space-borne Compton Polarimeter POLAR flight model with 100% polarized X-ray beams

H. L. Xiao; W. Hajdas; P. Socha; R. Marcinkowski; B. B. Wu; T. W. Bao; J. Y. Chai; Y. W. Dong; M. N. Kong; L. Li; Z. H. Li; J. T. Liu; H. L. Shi; L. M. Song; J. C. Sun; R. J. Wang; Y. H. Wang; X. Wen; S. L. Xiong; J. Zhang; L. Y. Zhang; S. N. Zhang; X. F. Zhang; Y. J. Zhang; F. Cadoux; M. Pohl; X. Wu; T. Batsch; D. Rybka; A. Rutczynska; J. Szabelski; A. Zwolinska; N. Gauvin; N. Produit; T. Bernasconi

arXiv · 1704.06173

Calibration of the Space-borne Compton Polarimeter POLAR flight model with 100% polarized X-ray beams

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Abstract

POLAR is space-borne detector designed for a precise measurement of gamma-ray polarization of the prompt emissions of Gamma-Ray Bursts in the energy range 50 keV - 500 keV. POLAR is a compact Compton polarimeter consisting of 40$\times$ 40 plastic scintillator bars read out by 25 multi-anode PMTs. In May 2015, we performed a series of tests of the POLAR flight model with 100\% polarized x-rays beams at the European Synchrotron Radiation Facility beam-line ID11 aming to study thresholds, crosstalk between channels and responses of POLAR flight model to polarized X-ray beams. In this paper we present the data analysis method and some analysis results. According the results, POLAR FM has good polarimetric capabilities.

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H. L. Xiao, W. Hajdas, P. Socha, R. Marcinkowski, B. B. Wu, T. W. Bao, J. Y. Chai, Y. W. Dong, M. N. Kong, L. Li, Z. H. Li, J. T. Liu, H. L. Shi, L. M. Song, J. C. Sun, R. J. Wang, Y. H. Wang, X. Wen, S. L. Xiong, J. Zhang, L. Y. Zhang, S. N. Zhang, X. F. Zhang, Y. J. Zhang, F. Cadoux, M. Pohl, X. Wu, T. Batsch, D. Rybka, A. Rutczynska, J. Szabelski, A. Zwolinska, N. Gauvin, N. Produit, T. Bernasconi. 2017-04-20. Calibration of the Space-borne Compton Polarimeter POLAR flight model with 100% polarized X-ray beams. https://arxiv.org/abs/1704.06173

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