Cosmic ray tests of a GEM-based TPC prototype operated in Ar-CF4-isobutane gas mixtures

M. Kobayashi; R. Yonamine; T. Tomioka; A. Aoza; H. Bito; K. Fujii; T. Higashi; K. Hiramatsu; K. Ikematsu; A. Ishikawa; Y. Kato; H. Kuroiwa; T. Matsuda; O. Nitoh; H. Ohta; K. Sakai; R. D. Settles; A. Sugiyama; H. Tsuji; T. Watanabe; H. Yamaoka; T. Yazu

doi:10.1016/j.nima.2011.02.042

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arXiv · 1008.5068

Cosmic ray tests of a GEM-based TPC prototype operated in Ar-CF4-isobutane gas mixtures

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Abstract

Argon with an admixture of CF4 is expected to be a good candidate for the gas mixture to be used for a time projection chamber (TPC) in the future linear collider experiment because of its small transverse diffusion of drift electrons especially under a strong magnetic field. In order to confirm the superiority of this gas mixture over conventional TPC gases we carried out cosmic ray tests using a GEM-based TPC operated mostly in Ar-CF4-isobutane mixtures under 0 - 1 T axial magnetic fields. The measured gas properties such as gas gain and transverse diffusion constant as well as the observed spatial resolution are presented.

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M. Kobayashi, R. Yonamine, T. Tomioka, A. Aoza, H. Bito, K. Fujii, T. Higashi, K. Hiramatsu, K. Ikematsu, A. Ishikawa, Y. Kato, H. Kuroiwa, T. Matsuda, O. Nitoh, H. Ohta, K. Sakai, R. D. Settles, A. Sugiyama, H. Tsuji, T. Watanabe, H. Yamaoka, T. Yazu. 2010-08-30. Cosmic ray tests of a GEM-based TPC prototype operated in Ar-CF4-isobutane gas mixtures. https://doi.org/10.1016/j.nima.2011.02.042

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