Beam induced space-charge effects in Time Projection Chambers in low-energy nuclear physics experiments

J. S. Randhawa; M. Cortesi; Y. Ayyad; W. Mittig; T. Ahn; D. Bazin; S. Beceiro-Novo; L. Carpenter; K. J. Cook; M. Dasgupta; S. Henderson; D. J. Hinde; J. J. Kolata; J. Sammut; C. Santamaria; N. Watwood; A. Yeck

doi:10.1016/j.nima.2019.162830

arXiv · 1907.06710

Beam induced space-charge effects in Time Projection Chambers in low-energy nuclear physics experiments

J. S. Randhawa·M. Cortesi·Y. Ayyad·W. Mittig·T. Ahn·D. Bazin·S. Beceiro-Novo·L. Carpenter·K. J. Cook·M. Dasgupta·S. Henderson·D. J. Hinde·J. J. Kolata·J. Sammut·C. Santamaria·N. Watwood·A. Yeck

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Abstract

Tracking capabilities in Time Projection Chambers (TPCs) are strongly dictated by the homogeneity of the drift field. Ion back-flow in various gas detectors, mainly induced by the secondary ionization processes during amplification, has long been known as a source of drift field distortion. Here, we report on beam-induced space-charge effects from the primary ionization process in the drift region in low-energy nuclear physics experiment with Active Target Time Projection Chamber (AT-TPC). A qualitative explanation of the observed effects is provided using detailed electron transport simulations. As ion mobility is a crucial factor in the space-charge effects, the need for a careful optimization of gas properties is highlighted. The impact of track distortion on tracking algorithm performance is also discussed.

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J. S. Randhawa, M. Cortesi, Y. Ayyad, W. Mittig, T. Ahn, D. Bazin, S. Beceiro-Novo, L. Carpenter, K. J. Cook, M. Dasgupta, S. Henderson, D. J. Hinde, J. J. Kolata, J. Sammut, C. Santamaria, N. Watwood, A. Yeck. 2019-07-15. Beam induced space-charge effects in Time Projection Chambers in low-energy nuclear physics experiments. https://doi.org/10.1016/j.nima.2019.162830

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