Experimental study on the performance of a THGEM detector for X-rays.

By expanding the applications of GEM detectors, a newer pattern of such detectors was introduced in 2004, named THGEM detectors. In this work, a sample of an X-ray detector was designed and constructed using 2 cm x 2 cm THGEMs domestically produced with a thickness of 250 µm, a hole diameter of 300 µm and a pitch of 500 µm, for the first time. The triple THGEM detector working in Ar/CO₂ gas mixture was characterized. Influence of gas pressure and gas mixture on gain of the detector was investigated. Results show the detector operated in a stable mode with no discharges. The gain of the detector increased with high voltage across the THGEM electrodes exponentially. This verified the performance of a detector as a proportional counter. Also, the detector's gain is maximum at Ar/CO₂ (80/20) gas mixture and voltage of 700 V applied to each multiplier. The detector is promising for localization applications such as particle physics experiments. [ABSTRACT FROM AUTHOR]