Development of a time projection chamber with micro-pixel electrodes

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 2003-11, Vol.513 (1), p.94-98
• Main Authors: Kubo, Hidetoshi, Miuchi, Kentaro, Nagayoshi, Tsutomu, Ochi, Atsuhiko, Orito, Reiko, Takada, Atsushi, Tanimori, Toru, Ueno, Masaru
• Format: Article
• Language: English
• Subjects: Gaseous detector; Micro-pattern detector; Time projection chamber
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2003.08.009

A time projection chamber (TPC) based on a gaseous chamber with micro-pixel electrodes (μ-PIC) has been developed for measuring three-dimensional tracks of charged particles. The μ-PIC with a detection area of 10×10 cm 2 consists of a double-sided printing circuit board. Anode pixels are formed with 0.4 mm pitch on strips aligned perpendicular to the cathode strips in order to obtain a two-dimensional position. In the TPC with drift length of 8 cm, 4 mm wide field cage electrodes are aligned at 1 mm spaces and a uniform electric field of about 0.4 kV/cm is produced. For encoding of the three-dimensional position a synchronous readout system has been developed using Field Programmable Gate Arrays with 40 MHz clock. This system enables us to reconstruct the three-dimensional track of the particle at successive points like a cloud chamber even at high event rate. The drift velocity of electrons in the TPC was measured with the tracks of cosmic muons for 3 days, during which the TPC worked stably with the gas gain of 3000. With a radioisotope of gamma-ray source the three-dimensional track of a Compton scattered electron was taken successfully.