Cosmic Ray Test of Mini-drift Thick Gas Electron Multiplier Chamber for   Transition Radiation Detector
  A thick gas electron multiplier (THGEM) chamber with an effective readout area of 10$\times$10 cm$^{2}$ and a 11.3 mm ionization gap has been tested along with two regular gas electron multiplier (GEM) chambers in a cosmic ray test system. The thick ionization gap makes the THGEM chamber a mini-drift chamber. This kind mini-drift THGEM chamber is proposed as part of a transition radiation detector (TRD) for identifying electrons at an Electron Ion Collider (EIC) experiment. Through this cosmic ray test, an efficiency larger than 94$\%$ and a spatial resolution $\sim$220 $\mu$m are achieved for the THGEM chamber at -3.65 kV. Thanks to its outstanding spatial resolution and thick ionization gap, the THGEM chamber shows excellent track reconstruction capability. The gain uniformity and stability of the THGEM chamber are also presented. 
S. Yang, S. Das, B. Buck, C. Li, T. Ljubicic, R. Majka, M. Shao, N.   Smirnov, G. Visser, Z. Xu, Y. Zhou
physics.ins-det hep-ex